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_messy.json

@@ -0,0 +1,35 @@
+{
+  "articles": [
+    {
+      "id": 201,
+      "score": 7.0,
+      "category": "Science & Space",
+      "rationale": "careful write-up of an amateur radio occultation measurement",
+      "is_paywalled_guess": false
+    },
+    {
+      "id": "202",
+      "score": "6",
+      "category": "Niche Corner",
+      "rationale": "mailing-list argument about tape drives, oddly gripping",
+      "is_paywalled_guess": "false"
+    },
+    {
+      "id": 203,
+      "score": 4
+    },
+    {
+      "id": 204,
+      "score": 12.5,
+      "category": "Top Stories",
+      "rationale": "model ignored the rubric ceiling here",
+      "is_paywalled_guess": false
+    },
+    {
+      "score": 9.0,
+      "category": "Top Stories",
+      "rationale": "no id at all, unusable"
+    },
+    "a bare string where an object belongs"
+  ]
+}