feat: Implement Prompt Builder functionality in Popup and Options

- Added a new "Prompt Builder" tab in the Popup for generating AI prompts with customizable parameters.
- Introduced new state variables for managing prompt styles, personas, formats, and models.
- Enhanced the Options page to fetch and display models based on the provided API key.
- Updated the actions and types to include the new 'prompt' action and its associated parameters.
- Implemented migration logic for legacy plaintext API keys to encrypted storage.
- Updated the getSystemPrompt function to incorporate prompt parameters for better instruction generation.
- Added tests for the new functionality, including context menu entries and prompt generation logic.

.claude/skills/resume-project/SKILL.md

@@ -0,0 +1,11 @@
+---
+name: resume-project
+description: Rebuild verified project state after a fresh session, compaction, interruption, agent handoff, or a request to continue or resume work. Use proactively before planning or editing when conversation history may be incomplete.
+allowed-tools: Read Grep Glob
+---
+
+1. Read `CLAUDE.md`, `docs/HANDOFF.md`, `docs/PROJECT_BRIEF.md` when present, and the active rules under `## Lessons`.
+2. Inspect the current git status and only the files named by the handoff or current task.
+3. Separate verified facts from stale or unverified handoff claims. Re-run the smallest relevant check if the status is uncertain.
+4. Return a state snapshot: objective, verified progress, changed paths, verification status, open risks, and one next smallest action.
+5. Update `docs/HANDOFF.md` only when new evidence changes the state. Do not implement the next action unless the user or task explicitly asks.