Rip out Ollama: direct_route only, no LLM layer

Pete moves to a remote host without Ollama access. Every source must
declare a direct_route channel; the classifier, explainer, semantic
dedup, !explain summaries, feed_hint, and the recent_headlines /
classification_log tables are gone. Deterministic dedup (canonical URL,
headline_norm, per-channel cooldown) remains.

internal/storage/schema.go

@@ -11,26 +11,12 @@ CREATE TABLE IF NOT EXISTS stories (
     url_canonical TEXT,
     headline_norm TEXT,
     source        TEXT NOT NULL,
-    feed_hint     TEXT,
     platforms     TEXT,
     channel       TEXT,
     classified    INTEGER NOT NULL DEFAULT 0,
     seen_at       INTEGER NOT NULL
 );
 
-CREATE TABLE IF NOT EXISTS recent_headlines (
-    guid       TEXT PRIMARY KEY,
-    headline   TEXT NOT NULL,
-    source     TEXT NOT NULL,
-    seen_at    INTEGER NOT NULL
-);
-
-CREATE TABLE IF NOT EXISTS classification_log (
-    guid       TEXT PRIMARY KEY,
-    result     TEXT NOT NULL,
-    logged_at  INTEGER NOT NULL
-);
-
 CREATE TABLE IF NOT EXISTS post_log (
     id            INTEGER PRIMARY KEY AUTOINCREMENT,
     guid          TEXT NOT NULL,