feat(feedback): add in-app issue reporting

[luoxuanzao]

Summary

• Add in-app issue reporting: a question-bubble button in the view header (and a "Submit feedback" command) opens a dialog that sends the user's note to the Qoder team through the SDK's one-shot qodercli feedback subprocess, reusing the plugin's resolved CLI path and enhanced PATH. Optionally attaches the current vault's runtime diagnostics (--workdir) and the active session id; a successful submit copies the returned request id to the clipboard.
• Why: reporting a problem previously meant leaving Obsidian and running the CLI by hand.
• Copy decisions: no intro paragraph above the textarea; user-facing strings name Qoderian (not qodercli) for the diagnostics description, email hint and sign-in label. Submissions are always explicit — nothing is reported automatically.

Verification

• npm run typecheck
• npm run lint
• npm run test — 163 suites / 3510 tests pass, incl. feedback-modal + submit-user-feedback + locales
• npm run build — covered by CI on this PR
• npm run release:check — covered by CI on this PR
• npm run audit:prod — covered by CI on this PR
• Tested live in Obsidian (dev vault): header button + command open the modal; fields render (textarea + 2000-char counter, optional email, diagnostics toggle); submit is disabled at 0 and >2000 chars; no real submission was performed during testing

Safety

• No credentials, private vault content, internal URLs, or personal paths are included
• User-visible changes are documented in CHANGELOG.md (added under [Unreleased])

Co-authored-by: QoderAI (Qwen 3.8 Max) qoder_ai@qoder.com