feat: unified message banner for all screens

CLAUDE.md

@@ -58,13 +58,10 @@ scripts/safe-cargo.sh +nightly fmt --all
 
 ## Coding Conventions
 
-### Parameter ordering
+### General rules
 
-When a method takes `&AppContext` (or `Option<&AppContext>`), place it as the first parameter after `self`. Example:
-
-```rust
-fn remove_selected_utxos(&mut self, context: Option<&AppContext>, selected: &BTreeMap<...>) -> Result<(), String>
-```
+* When a method takes `&AppContext` (or `Option<&AppContext>`), place it as the first parameter after `self`.
+* Screen constructors handle errors internally via `MessageBanner` and return `Self` with degraded state. Keep `create_screen()` clean — no error handling at callsites.
 
 ## Architecture Overview
 
@@ -176,7 +173,9 @@ response.inner.update(&mut self.amount);
 
 ## Message Display
 
-User-facing messages use `MessageBanner` (`src/ui/components/message_banner.rs`). Global banners are rendered centrally by `island_central_panel()` — `AppState::update()` sets them automatically for backend task results. Screens only override `display_message()` for side-effects. See the component's doc comments and `docs/ai-design/2026-02-17-unified-messages/` for details.
+User-facing messages (errors, warnings, success, infos) use `MessageBanner` (`src/ui/components/message_banner.rs`). Global banners are rendered centrally by `island_central_panel()` — `AppState::update()` sets them automatically for backend task results. When using `MessageBanner::set_global()`, no guard is needed — it is idempotent and automatically logs at the appropriate level (error/warn/debug). Screens only override `display_message()` for side-effects. See the component's doc comments and `docs/ai-design/2026-02-17-unified-messages/` for details.
+
+**BannerHandle lifecycle**: Screens that run backend tasks typically store a `refresh_banner: Option<BannerHandle>` field. On task dispatch, set it via `MessageBanner::set_global()` with an info/progress message. In `display_message()` (called as a side-effect by AppState), dismiss the progress banner via `self.refresh_banner.take_and_clear()` (from `OptionBannerExt`). Simply setting the field to `None` would leak the banner — `take_and_clear()` removes it from the egui context. AppState handles displaying the actual result banner.
 
 ## Database
 

docs/ai-design/2026-02-27-banner-review-fixes/pr-604-review-guide.md

@@ -0,0 +1,119 @@
+# PR #604 — Manual Review Guide
+
+Key files for manual review: architectural decisions, reusable patterns, and behavioral changes.
+Files that merely apply patterns defined here are excluded (~57 files).
+
+## 1. Core Infrastructure
+
+### [`src/ui/components/message_banner.rs`](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-5c97c5af2fd0a32afba3e66e5f6a5f7acafb9a73da0d3b89a92f8fc9fca06a35)
+
+Heart of the PR. All other changes depend on patterns defined here.
+
+| What | Lines | Link |
+|---|---|---|
+| `set_global` idempotency change — no longer resets existing banners | L292–333 | [L292](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-5c97c5af2fd0a32afba3e66e5f6a5f7acafb9a73da0d3b89a92f8fc9fca06a35R292) |
+| `replace_global` docs + empty-text semantics | L338–391 | [L338](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-5c97c5af2fd0a32afba3e66e5f6a5f7acafb9a73da0d3b89a92f8fc9fca06a35R338) |
+| `with_details` now takes `impl Debug` instead of `&str` | L190–210 | [L190](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-5c97c5af2fd0a32afba3e66e5f6a5f7acafb9a73da0d3b89a92f8fc9fca06a35R190) |
+| `ResultBannerExt` — `or_show_error()` on `Result` | L715–740 | [L715](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-5c97c5af2fd0a32afba3e66e5f6a5f7acafb9a73da0d3b89a92f8fc9fca06a35R715) |
+| `OptionBannerExt` — `or_show_error()` + `take_and_clear()` on `Option<BannerHandle>` | L742–770 | [L742](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-5c97c5af2fd0a32afba3e66e5f6a5f7acafb9a73da0d3b89a92f8fc9fca06a35R742) |
+| SEC-003: Eviction log no longer includes message text | L327–330 | [L327](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-5c97c5af2fd0a32afba3e66e5f6a5f7acafb9a73da0d3b89a92f8fc9fca06a35R327) |
+
+**Review focus**: Verify the idempotency change in `set_global` (old behavior reset existing banners, new behavior is a no-op). This is a subtle semantic change that affects all callers.
+
+## 2. Behavioral / Architectural Decisions
+
+### [`src/ui/mod.rs` — ScreenLike trait](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-d64f1e2614b0de74ea77854bc2fb944deaaa5b40a4e37b91a81a94da9bd5ebf8R840)
+
+`display_task_result` default changed from showing "Success" banner to **no-op**. Breaking behavioral change — screens that relied on the default now silently swallow success results.
+
+| What | Lines | Link |
+|---|---|---|
+| `display_task_result` default → no-op | L840–857 | [L840](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-d64f1e2614b0de74ea77854bc2fb944deaaa5b40a4e37b91a81a94da9bd5ebf8R840) |
+
+**Review focus**: Verify that AppState now handles success banners centrally, and no screen was relying on the old default `display_message("Success", Success)`.
+
+### [`src/app.rs` — Connection banner + network switch](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-8c6f1be9c6b6eb6dc2c76e6a6f2706d76f81aad0ff222c5a9ef4eab78acee7b5)
+
+New `update_connection_banner()` state machine and `clear_all_global` on network switch.
+
+| What | Lines | Link |
+|---|---|---|
+| `previous_connection_state` + `connection_banner_handle` fields | L93–99 | [L93](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-8c6f1be9c6b6eb6dc2c76e6a6f2706d76f81aad0ff222c5a9ef4eab78acee7b5R93) |
+| `clear_all_global` on network switch + INTENTIONAL comment | L875–896 | [L875](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-8c6f1be9c6b6eb6dc2c76e6a6f2706d76f81aad0ff222c5a9ef4eab78acee7b5R875) |
+| `update_connection_banner()` — Disconnected/Syncing/Synced FSM | L898–934 | [L898](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-8c6f1be9c6b6eb6dc2c76e6a6f2706d76f81aad0ff222c5a9ef4eab78acee7b5R898) |
+
+**Review focus**: The FSM uses `OverallConnectionState` equality to avoid redundant banner updates. Verify the state transitions cover all edge cases (e.g., rapid Disconnected→Syncing→Disconnected).
+
+### [`src/context/connection_status.rs`](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-75d4306c0e7eca30d7e0dbb01b6f6b3d3b3af1e65a22e6de68aa6c92d9b3779f)
+
+Removed error-string-matching logic (`contains("Failed to get best chain lock...")`). Verify this dead code removal is safe — the connection banner in `app.rs` now handles disconnected state via the FSM instead.
+
+| What | Lines | Link |
+|---|---|---|
+| Removed string-matching error handler | L295–327 | [L295](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-75d4306c0e7eca30d7e0dbb01b6f6b3d3b3af1e65a22e6de68aa6c92d9b3779f) |
+
+## 3. Reusable Pattern Examples (one representative each)
+
+### [`src/ui/tokens/mod.rs` — Shared helpers](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-0e09ce3e1e56a10a8d2cef2e29e7addb8e5a4dff5f78b8e15c50cdc94ef53e06R16)
+
+Defines 3 shared helpers used by ~15 token screens. This is where the DRY pattern originates.
+
+| What | Lines | Link |
+|---|---|---|
+| `load_identities_with_banner()` | L22–28 | [L22](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-0e09ce3e1e56a10a8d2cef2e29e7addb8e5a4dff5f78b8e15c50cdc94ef53e06R22) |
+| `set_error_banner()` | L31–34 | [L31](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-0e09ce3e1e56a10a8d2cef2e29e7addb8e5a4dff5f78b8e15c50cdc94ef53e06R31) |
+| `validate_signing_key()` — `&Option<T>` → `Option<&T>` | L40–56 | [L40](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-0e09ce3e1e56a10a8d2cef2e29e7addb8e5a4dff5f78b8e15c50cdc94ef53e06R40) |
+
+### [`src/ui/tokens/claim_tokens_screen.rs` — Constructor error handling](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-e5e6e8b6d4ffd3f1fba60f4bbb7c2e9a6a5db3b2aa3b0acfe7c4bc01fd2a88b5)
+
+Best example of the SEC-001 fix pattern — eliminated `.expect()` panics in constructors, replaced with `or_show_error()` + degraded state.
+
+| What | Lines | Link |
+|---|---|---|
+| Constructor: single DB load + `or_show_error` + `.or_else` fallback | L77–107 | [L77](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-e5e6e8b6d4ffd3f1fba60f4bbb7c2e9a6a5db3b2aa3b0acfe7c4bc01fd2a88b5R77) |
+| Status enum: `WaitingForResult(u64)` → `WaitingForResult` (dropped timestamp) | L45–50 | [L45](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-e5e6e8b6d4ffd3f1fba60f4bbb7c2e9a6a5db3b2aa3b0acfe7c4bc01fd2a88b5R45) |
+
+### [`src/ui/identities/add_existing_identity_screen.rs` — `AddIdentityStatus::Error` variant](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-ce4b3e7e4e4beb1a3c39f4def2f6a86a86a3a3a97e64bbd29b9fa5f1db34c7e7)
+
+Shows the PROJ-005 pattern — status enums no longer carry error strings (moved to global banner). Also shows constructor error handling via `MessageBanner::set_global`.
+
+| What | Lines | Link |
+|---|---|---|
+| `AddIdentityStatus::Error` (unit variant, no string) | L85–88 | [L85](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-ce4b3e7e4e4beb1a3c39f4def2f6a86a86a3a3a97e64bbd29b9fa5f1db34c7e7R85) |
+| Constructor: init error → `set_global` | L126–128 | [L126](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-ce4b3e7e4e4beb1a3c39f4def2f6a86a86a3a3a97e64bbd29b9fa5f1db34c7e7R126) |
+
+### [`src/ui/wallets/send_screen.rs` — BannerHandle lifecycle](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-4b2fd2b6b35fe1d83a5c0e1a80e8a51e03ba4c3f03e5da1bb7498fe43e34e57f)
+
+Most complete example of the `BannerHandle` lifecycle pattern — progress banner with elapsed time, clearing on result, and the `set_send_progress_banner` helper.
+
+| What | Lines | Link |
+|---|---|---|
+| `send_banner: Option<BannerHandle>` field | L389–392 | [L389](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-4b2fd2b6b35fe1d83a5c0e1a80e8a51e03ba4c3f03e5da1bb7498fe43e34e57fR389) |
+| `set_send_progress_banner()` — take_and_clear + set_global + with_elapsed | L650–660 | [L650](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-4b2fd2b6b35fe1d83a5c0e1a80e8a51e03ba4c3f03e5da1bb7498fe43e34e57fR650) |
+
+## 4. Conventions / Docs
+
+### [`CLAUDE.md`](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-82d8aa1d8fd8d9b71c3cf5e7fcade1d8697cc47c6df2e1b0c77ed5b0f01e5e93)
+
+Updated conventions affect all future development.
+
+| What | Lines | Link |
+|---|---|---|
+| Constructor error handling convention | L58–63 | [L58](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-82d8aa1d8fd8d9b71c3cf5e7fcade1d8697cc47c6df2e1b0c77ed5b0f01e5e93R58) |
+| `BannerHandle` lifecycle docs | L173–181 | [L173](https://github.com/dashpay/dash-evo-tool/pull/604/files#diff-82d8aa1d8fd8d9b71c3cf5e7fcade1d8697cc47c6df2e1b0c77ed5b0f01e5e93R173) |
+
+## Summary: 8 files to review, ~57 files skipped
+
+| Priority | File | What to verify |
+|---|---|---|
+| 🔴 | `message_banner.rs` | `set_global` idempotency change, extension traits |
+| 🔴 | `src/ui/mod.rs` | `display_task_result` default → no-op |
+| 🔴 | `src/app.rs` | Connection banner FSM, `clear_all_global` on switch |
+| 🟡 | `connection_status.rs` | Error-string-matching removal safety |
+| 🟡 | `tokens/mod.rs` | Shared helpers (`validate_signing_key` signature) |
+| 🟢 | `claim_tokens_screen.rs` | Constructor pattern example |
+| 🟢 | `add_existing_identity_screen.rs` | Status enum + init error pattern |
+| 🟢 | `send_screen.rs` | BannerHandle lifecycle pattern |
+| 📄 | `CLAUDE.md` | Convention accuracy |
+
+The remaining ~57 files are mechanical applications of these patterns — `take_and_clear()`, `or_show_error()`, status enum simplification, and `error_message` field removal. If the patterns above look correct, those files are correct by construction.