Add go-expect based integration test for password resets

[Askir]

This also changes to prefer the TIGER_CONFIG_DIR env var over the keyring if it is set.
This was necessary to give an option for the integration test not use the system keyring, but I think it generally makes sense to do this?

Output looks like this:

go test ./internal/tiger/cmd -v -run TestDbConnectPasswordResetIntegration -timeout 30m
=== RUN   TestDbConnectPasswordResetIntegration
Set api_url = https://console.cloud.timescale.com/public/api/v1
    integration_test.go:2047: Using temporary config directory: /var/folders/db/hb2zr45j3l3btft0bv249vhm0000gn/T/tiger-integration-test-1023195604
=== RUN   TestDbConnectPasswordResetIntegration/Login
    integration_test.go:2083: Logging in with public key: 01KC6QNV...
=== RUN   TestDbConnectPasswordResetIntegration/CreateService
    integration_test.go:2103: Creating service for password reset test
    integration_test.go:2119: Created service with ID: baodc92dti
=== NAME  TestDbConnectPasswordResetIntegration
    integration_test.go:2124: Built tiger binary at: /var/folders/db/hb2zr45j3l3btft0bv249vhm0000gn/T/tiger-integration-test-1023195604/tiger
=== RUN   TestDbConnectPasswordResetIntegration/SubprocessLogin
    integration_test.go:2129: Running tiger auth login in subprocess environment
    integration_test.go:2140: Subprocess auth login output: Validating API key...
        Successfully logged in (project: wyuqu2ystg)

        🎉 Next steps:
        • Install MCP server for your favorite AI coding tool: tiger mcp install
        • List existing services: tiger service list
        • Create a new service: tiger service create
=== RUN   TestDbConnectPasswordResetIntegration/VerifyInitialConnection
    integration_test.go:2148: Verifying initial connection works before deleting password
    integration_test.go:2173: Waiting for psql prompt...
psql (14.18 (Homebrew), server 17.7 (Ubuntu 17.7-3.pgdg22.04+1))
WARNING: psql major version 14, server major version 17.
         Some psql features might not work.
SSL connection (protocol: TLSv1.3, cipher: TLS_AES_256_GCM_SHA384, bits: 256, compression: off)
Type "help" for help.

tsdb=>    integration_test.go:2178: Got psql prompt - connection works!
    integration_test.go:2184: Initial connection verified successfully
=== RUN   TestDbConnectPasswordResetIntegration/DeleteStoredPassword
    integration_test.go:2192: Deleting stored password to trigger recovery flow
    integration_test.go:2227: Password removed from storage
=== RUN   TestDbConnectPasswordResetIntegration/InteractivePasswordReset
    integration_test.go:2235: Running interactive password reset flow
    integration_test.go:2259: Waiting for menu prompt...
Warning: could not retrieve stored password: no matching entry found in .pgpass file
failed to connect to `user=tsdbadmin database=tsdb`: 3.231.107.230:32894 (baodc92dti.wyuqu2ystg.tsdb.cloud.timescale.com): failed SASL auth: FATAL: password authentication failed for user "tsdbadmin" (SQLSTATE 28P01)
Stored password is likely invalid or expired.

What would you like to do?    integration_test.go:2264: Got menu prompt
    integration_test.go:2267: Selecting option 2 (Update/reset password)
    integration_test.go:2271: Waiting for password prompt...


  1. Enter password manually
> 2. Update/reset password
  3. Exit

Enter new password    integration_test.go:2276: Got password prompt
    integration_test.go:2279: Sending empty password to auto-generate
    integration_test.go:2283: Waiting for success message...
 (leave empty to generate):
Successfully generated a new password.
Password saved to ~/.pgpass for automatic authentication
To view your new password, run:
	 tiger service get baodc92dti --with-password
✅ Master password for 'tsdbadmin' user updated successfully    integration_test.go:2288: Got success message
    integration_test.go:2291: Waiting for psql to launch...
    integration_test.go:2296: Sending \q to exit psql
    integration_test.go:2305: Interactive password reset completed
=== RUN   TestDbConnectPasswordResetIntegration/VerifyPasswordReset
    integration_test.go:2313: Verifying password was reset successfully
    integration_test.go:2330: Password reset verified - connection successful
=== RUN   TestDbConnectPasswordResetIntegration/DeleteService
    integration_test.go:2338: Deleting service: baodc92dti
    integration_test.go:2353: Service deleted successfully
=== NAME  TestDbConnectPasswordResetIntegration
    integration_test.go:2059: Cleaning up authentication
--- PASS: TestDbConnectPasswordResetIntegration (65.10s)
    --- PASS: TestDbConnectPasswordResetIntegration/Login (0.56s)
    --- PASS: TestDbConnectPasswordResetIntegration/CreateService (51.77s)
    --- PASS: TestDbConnectPasswordResetIntegration/SubprocessLogin (0.85s)
    --- PASS: TestDbConnectPasswordResetIntegration/VerifyInitialConnection (2.91s)
    --- PASS: TestDbConnectPasswordResetIntegration/DeleteStoredPassword (0.33s)
    --- PASS: TestDbConnectPasswordResetIntegration/InteractivePasswordReset (4.37s)
    --- PASS: TestDbConnectPasswordResetIntegration/VerifyPasswordReset (1.30s)
    --- PASS: TestDbConnectPasswordResetIntegration/DeleteService (1.45s)
PASS
ok  	github.com/timescale/tiger-cli/internal/tiger/cmd	(cached)