feat(temporal): add date extraction, heuristic range parsing, and temporal scoring

Pure functions for temporal search: extract_note_date from frontmatter/filename,
temporal_score for proximity decay, parse_date_range_heuristic for natural language
temporal keywords, and parse_date_range_from_json for LLM orchestrator output.
33 unit tests covering all functions.

Author: devwhodevs

Cargo.lock

@@ -28,7 +28,7 @@ indicatif = "0.17"
 sqlite-vec = "0.1.8-alpha.1"
 zerocopy = { version = "0.7", features = ["derive"] }
 rayon = "1"
-time = "0.3"
+time = { version = "0.3", features = ["parsing", "formatting", "macros"] }
 strsim = "0.11"
 ignore = "0.4"
 rmcp = { version = "1.2", features = ["transport-io"] }

Cargo.toml

@@ -17,6 +17,7 @@ pub mod search;
 pub mod serve;
 pub mod store;
 pub mod tags;
+pub mod temporal;
 pub mod vecstore;
 pub mod watcher;
 pub mod writer;