feat: add blog draft generator and fix broken routes

Blog drafting section (dev-only):
- BlogDraftGenerator gathers project data (gaps, proposals, stats) as
  context and calls Claude to produce Medium-style blog posts
- DB schema: blog_drafts table with title, content, tags, cost tracking
- Web UI: list, generate (async with live preview), detail (rendered +
  source toggle), edit, and export routes
- 6 writing styles: deep-dive, overview, opinion, listicle, comparison,
  series-post
- Nav link added to sidebar under Proposals

Bug fixes found via route testing (scripts/test_all_routes.py):
- /authors/<id>: Draft.status → Draft.states (correct attribute name)
- /false-positives: add missing `import re` in ratings.py

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

src/ietf_analyzer/db.py

@@ -218,6 +218,26 @@ CREATE TABLE IF NOT EXISTS proposal_gaps (
 
 CREATE INDEX IF NOT EXISTS idx_proposal_gaps_gap ON proposal_gaps(gap_id);
 
+-- Blog drafts (generated or manually written)
+CREATE TABLE IF NOT EXISTS blog_drafts (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    title TEXT NOT NULL,
+    subtitle TEXT DEFAULT '',
+    slug TEXT NOT NULL UNIQUE,
+    status TEXT DEFAULT 'draft',
+    style TEXT DEFAULT 'deep-dive',
+    tags TEXT DEFAULT '[]',
+    topic TEXT DEFAULT '',
+    instructions TEXT DEFAULT '',
+    content_md TEXT DEFAULT '',
+    model_used TEXT DEFAULT '',
+    input_tokens INTEGER DEFAULT 0,
+    output_tokens INTEGER DEFAULT 0,
+    cost_usd REAL DEFAULT 0,
+    created_at TEXT,
+    updated_at TEXT
+);
+
 -- Annotations (user notes + tags per draft)
 CREATE TABLE IF NOT EXISTS annotations (
     id INTEGER PRIMARY KEY AUTOINCREMENT,
@@ -1169,6 +1189,62 @@ class Database:
         ).fetchall()
         return [dict(r) for r in rows]
 
+    # --- Blog Drafts ---
+
+    def all_blog_drafts(self) -> list[dict]:
+        rows = self.conn.execute(
+            "SELECT * FROM blog_drafts ORDER BY updated_at DESC"
+        ).fetchall()
+        return [dict(r) for r in rows]
+
+    def get_blog_draft(self, draft_id: int) -> dict | None:
+        row = self.conn.execute(
+            "SELECT * FROM blog_drafts WHERE id = ?", (draft_id,)
+        ).fetchone()
+        return dict(row) if row else None
+
+    def upsert_blog_draft(self, draft: dict) -> int:
+        """Insert or update a blog draft. Returns the draft ID."""
+        now = datetime.now(timezone.utc).isoformat()
+        if draft.get("id"):
+            self.conn.execute(
+                """UPDATE blog_drafts SET title=?, subtitle=?, slug=?, status=?,
+                   style=?, tags=?, topic=?, instructions=?, content_md=?,
+                   model_used=?, input_tokens=?, output_tokens=?, cost_usd=?,
+                   updated_at=?
+                   WHERE id=?""",
+                (draft["title"], draft.get("subtitle", ""), draft["slug"],
+                 draft.get("status", "draft"), draft.get("style", "deep-dive"),
+                 json.dumps(draft.get("tags", [])), draft.get("topic", ""),
+                 draft.get("instructions", ""), draft.get("content_md", ""),
+                 draft.get("model_used", ""), draft.get("input_tokens", 0),
+                 draft.get("output_tokens", 0), draft.get("cost_usd", 0),
+                 now, draft["id"]),
+            )
+            self.conn.commit()
+            return draft["id"]
+        else:
+            cur = self.conn.execute(
+                """INSERT INTO blog_drafts (title, subtitle, slug, status, style,
+                   tags, topic, instructions, content_md, model_used,
+                   input_tokens, output_tokens, cost_usd, created_at, updated_at)
+                   VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)""",
+                (draft["title"], draft.get("subtitle", ""), draft["slug"],
+                 draft.get("status", "draft"), draft.get("style", "deep-dive"),
+                 json.dumps(draft.get("tags", [])), draft.get("topic", ""),
+                 draft.get("instructions", ""), draft.get("content_md", ""),
+                 draft.get("model_used", ""), draft.get("input_tokens", 0),
+                 draft.get("output_tokens", 0), draft.get("cost_usd", 0),
+                 now, now),
+            )
+            self.conn.commit()
+            return cur.lastrowid
+
+    def delete_blog_draft(self, draft_id: int) -> bool:
+        cur = self.conn.execute("DELETE FROM blog_drafts WHERE id = ?", (draft_id,))
+        self.conn.commit()
+        return cur.rowcount > 0
+
     # --- Refs ---
 
     def insert_refs(self, draft_name: str, refs: list[tuple[str, str]]) -> None: