Initial commit: The Daily EPUB full implementation

Full implementation of a personalized daily newspaper delivered as an
EPUB.

Articles are pulled from a local self-hosted Miniflux instance, enriched
with comments, summarized and filtered by DeepSeek AI, and then
assembled into two EPUB editions: standard and optimized for the Xteink
X4 e-ink reader. Both are served by the local self-hosted BookOrbit OPDS
server in a separate library. Then the X4 edition is futher converted to
XTC format and served over a separate OPDS server hosted by the Rust
binary. Runs are tracked in a local SQLite database so runs are
idempotent per date.

Full documentation of the plan is in docs/plans and setup and install
instructions are in the README.md file.

tests/fixtures/deepseek_score_batch.json

@@ -0,0 +1,32 @@
+{
+  "articles": [
+    {
+      "id": 101,
+      "score": 8.5,
+      "category": "Tech & Engineering",
+      "rationale": "first-hand 40TB Postgres migration with numbers, failures and rollback plan",
+      "is_paywalled_guess": false
+    },
+    {
+      "id": 102,
+      "score": 3.0,
+      "category": "AI & Machine Learning",
+      "rationale": "model release announcement, no independent evaluation",
+      "is_paywalled_guess": false
+    },
+    {
+      "id": 103,
+      "score": 6.5,
+      "category": "Boston & Local",
+      "rationale": "MBTA slow-zone data analysis with original charts",
+      "is_paywalled_guess": false
+    },
+    {
+      "id": 104,
+      "score": 5.0,
+      "category": "Culture & Essays",
+      "rationale": "promising essay on typesetting, body appears truncated",
+      "is_paywalled_guess": true
+    }
+  ]
+}