fix(app): surface uninstall failures instead of reporting false success

[martin-helmich]

Problem

mw app uninstall <id> --force printed both an error and Process completed successfully, and appeared to exit 0, even when the uninstall actually failed with HTTP 412 (the app has a linked primary database). Scripts could not detect the failure, and the reason was not surfaced.

Root cause

DeleteBaseCommand.exec() caught errors thrown by deleteResource() and marked the step as failed, but then still called process.complete(...). The SimpleProcessRenderer (used in non-TTY/CI contexts) unconditionally writes Completed: Process completed successfully in complete(), so a failed deletion was reported as a success.

Fix

• DeleteBaseCommand now calls process.error(err) in the catch branch instead of process.complete(...), so the failure is surfaced. It keeps ux.exit(1) to guarantee a non-zero exit code. This corrects all delete commands.
• app uninstall now maps the HTTP 412 (linked primary database) to an actionable message — "cannot uninstall: app has a linked primary database — unlink or repurpose it first ..." — while passing every other error through unchanged (with the original error attached as cause).

Tests

• src/lib/basecommands/DeleteBaseCommand.test.tsx — asserts that on a failing deletion the command does not report success, surfaces the error via process.error, and exits non-zero (ExitError with oclif.exit === 1); and that a successful deletion still reports success and does not exit non-zero.
• src/commands/app/uninstall.test.ts — covers the 412 → primary-database message mapping and pass-through of other errors.

Closes #1970

🤖 Generated with Claude Code

[martin-helmich]

Unsure if this can't be done more elegantly. Also don't know if there are other conditions in which a 412 status code might arise. Should investigate if there's a more specific error code in the response body that we could filter for.