scaffold tasks extension

Empty skeleton mirroring the events extension layout: config/manifest,
pyproject + Makefile + ruff/mypy config, FastAPI routers wired into
tasks_ext, NostrClient bootstrap stubs, and an empty static/routes.json.

Models, migrations, CRUD, Nostr publisher/sync, and the API/template
layers land in follow-up commits.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

config.json

@@ -0,0 +1,25 @@
+{
+  "id": "tasks",
+  "version": "0.1.0",
+  "name": "Tasks",
+  "repo": "https://git.atitlan.io/aiolabs/tasks",
+  "short_description": "Recurring tasks and chore-tracking, published over Nostr",
+  "description": "",
+  "tile": "/tasks/static/image/tasks.png",
+  "min_lnbits_version": "1.4.1",
+  "contributors": [
+    {
+      "name": "padreug",
+      "uri": "https://git.atitlan.io/padreug",
+      "role": "Developer"
+    }
+  ],
+  "images": [],
+  "description_md": "https://git.atitlan.io/aiolabs/tasks/raw/branch/main/description.md",
+  "terms_and_conditions_md": "https://git.atitlan.io/aiolabs/tasks/raw/branch/main/toc.md",
+  "license": "MIT",
+  "paid_features": "",
+  "tags": ["Productivity"],
+  "donate": "",
+  "hidden": false
+}