feat: v0.2.0 — Joplin import, ChatGPT Projects, --project filter

Core features:
- Add `joplin` command: syncs exported Markdown to Joplin via local REST API
- Notebooks auto-created per provider+project (e.g. "ChatGPT - My Project")
- Idempotent: notes updated (not duplicated) on re-run; note ID tracked in manifest
- Add `--project` filter to `export` and `list` commands (substring or 'none')
- Add ChatGPT Projects support via CHATGPT_PROJECT_IDS env var

Config:
- Add JOPLIN_API_TOKEN, JOPLIN_API_URL, JOPLIN_REQUEST_TIMEOUT
- Version now read from importlib.metadata (single source of truth: pyproject.toml)
- Bump version to 0.2.0

Quality:
- Explicit Timeout handling in JoplinClient with actionable error messages
- token validation (validate_token) separate from connectivity (ping)
- Remove debug_auth.py, debug_claude.py, and untracked .har file
- Add *.har to .gitignore (may contain auth cookies/session tokens)
- Update README, CHANGELOG, FUTURE.md to reflect v0.2.0

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

CHANGELOG.md

@@ -3,6 +3,16 @@
 All notable changes to this project will be documented here.
 Format follows [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
+## [0.2.0] - Unreleased
+### Added
+- Joplin import automation: `joplin` command syncs exported Markdown files to Joplin as notes
+- Notebooks created automatically per provider+project (`ChatGPT - My Project`, etc.)
+- Re-running is safe: notes are updated, not duplicated (Joplin note ID stored in manifest)
+- `JOPLIN_API_TOKEN`, `JOPLIN_API_URL`, `JOPLIN_REQUEST_TIMEOUT` config variables
+- Configurable request timeout with clear error messages and actionable hints on timeout
+- `--project` filter on `export` and `list` commands (case-insensitive substring or `none`)
+- ChatGPT Projects support via `CHATGPT_PROJECT_IDS` env var
+
 ## [0.1.0] - Unreleased
 ### Added
 - Initial implementation: ChatGPT and Claude export via internal web APIs