feat: config profiles, integrations system, and DaVinci Resolve export

.gitignore

@@ -8,6 +8,7 @@ dist/
 # Data directory
 data/
 .podcli/
+.podcli-home
 presets/
 
 # Environment

CONTRIBUTING.md

@@ -0,0 +1,54 @@
+# Contributing to podcli
+
+Thank you for helping improve podcli. This project is AGPL-3.0 — contributions are welcome under the same license.
+
+## Development setup
+
+```bash
+./setup.sh
+npm install
+npm run build
+```
+
+Python backend lives in `backend/`. TypeScript MCP server and Web UI live in `src/`.
+
+## Project layout
+
+| Path                                    | Purpose                                                         |
+| --------------------------------------- | --------------------------------------------------------------- |
+| `.podcli/`                              | Config home (knowledge, presets, assets, settings) — gitignored |
+| `data/`                                 | Runtime data (cache, output, working) — gitignored              |
+| `backend/config/paths.py`               | Canonical path resolution (Python)                              |
+| `src/config/paths.ts`                   | Path resolution for Node (must stay aligned)                    |
+| `backend/config_bundle.py`              | Portable profile export/import                                  |
+| `backend/services/transcript_packer.py` | Transcript cache keys + packed markdown                         |
+
+## Before you open a PR
+
+1. Run tests: `python3 -m unittest discover -s tests -v`
+2. Run TypeScript build: `npm run build`
+3. If you change paths, env vars, or cache layout, update `README.md` and add a note to the config migration logic.
+4. Keep diffs focused — one feature or fix per PR when possible.
+
+## Path and cache conventions
+
+- **Config home** (`PODCLI_HOME` or `.podcli-home` marker): portable settings only.
+- **Data dir** (`PODCLI_DATA` or `data/`): transcripts cache, outputs, temp files.
+- **Transcript cache**: `data/cache/transcripts/{16-char-hash}.json` — same hash algorithm in Python (`compute_cache_hash`) and TypeScript (`TranscriptCache`).
+
+Do not reintroduce a separate CLI-only cache path without updating both sides.
+
+## Adding an integration
+
+1. Create `backend/services/integrations/<name>/` with `IntegrationBase` subclass.
+2. Register in that package’s `__init__.py`.
+3. Add MCP tool wiring in `src/server.ts` (or a thin handler) and optional UI toggle at `/integrations.html`.
+
+## Security
+
+- Config import uses zip path validation (`_safe_extract_zip`). Do not replace with raw `extractall` on untrusted archives.
+- Do not commit `.env`, API keys, or personal media under `.podcli/` or `data/`.
+
+## Questions
+
+Open a GitHub issue with reproduction steps for bugs, or a short design note for larger features.