feat(timeline): add entity-direct seeding (issue:N, mr:N syntax)

Adds issue:N / i:N / mr:N / m:N query syntax to bypass hybrid search
and seed the timeline directly from a known entity. All discussions for
the entity are gathered without needing Ollama.

- parse_timeline_query() detects entity-direct patterns
- resolve_entity_by_iid() resolves IID to EntityRef with ambiguity handling
- seed_timeline_direct() gathers all discussions for the entity
- 20 new tests (5 resolve, 6 direct seed, 9 parse)
- Updated CLI help text and robot-docs manifest

src/main.rs

@@ -2345,13 +2345,17 @@ fn handle_robot_docs(robot_mode: bool, brief: bool) -> Result<(), Box<dyn std::e
             "example": "lore completions bash > ~/.local/share/bash-completion/completions/lore"
         },
         "timeline": {
-            "description": "Chronological timeline of events matching a keyword query",
+            "description": "Chronological timeline of events matching a keyword query or entity reference",
             "flags": ["<QUERY>", "-p/--project", "--since <duration>", "--depth <n>", "--expand-mentions", "-n/--limit", "--fields <list>", "--max-seeds", "--max-entities", "--max-evidence"],
-            "example": "lore --robot timeline '<keyword>' --since 30d",
+            "query_syntax": {
+                "search": "Any text -> hybrid search seeding (FTS + vector)",
+                "entity_direct": "issue:N, i:N, mr:N, m:N -> direct entity seeding (no search, no Ollama)"
+            },
+            "example": "lore --robot timeline issue:42",
             "response_schema": {
                 "ok": "bool",
                 "data": {"entities": "[{type:string, iid:int, title:string, project_path:string}]", "events": "[{timestamp:string, type:string, entity_type:string, entity_iid:int, detail:string}]", "total_events": "int"},
-                "meta": {"elapsed_ms": "int"}
+                "meta": {"elapsed_ms": "int", "search_mode": "string (hybrid|lexical|direct)"}
             },
             "fields_presets": {"minimal": ["timestamp", "type", "entity_iid", "detail"]}
         },