feat(agent): add semantic detection and resumable sessions

Use declarative screen evidence beneath exact hooks so more AI clients surface working and blocked states, while safe resume and fork commands preserve agent sessions across restarts.

Cargo.lock

@@ -4600,6 +4600,7 @@ dependencies = [
  "pollster 0.4.0",
  "pulldown-cmark",
  "pulldown-latex",
+ "regex",
  "rfd",
  "russh",
  "russh-sftp",
@@ -6452,9 +6453,9 @@ dependencies = [
 
 [[package]]
 name = "regex"
-version = "1.12.3"
+version = "1.13.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e10754a14b9137dd7b1e3e5b0493cc9171fdd105e0ab477f51b72e7f3ac0e276"
+checksum = "f020237b6c8eed93db2e2cb53c00c60a8e1bc73da7d073199a1180401450218d"
 dependencies = [
  "aho-corasick",
  "memchr",
@@ -6475,9 +6476,9 @@ dependencies = [
 
 [[package]]
 name = "regex-syntax"
-version = "0.8.6"
+version = "0.8.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "caf4aa5b0f434c91fe5c7f1ecb6a5ece2130b02ad2a590589dda5146df959001"
+checksum = "d6f6ff9a378485b298a5286656da665ba74413d36db0979633275d2e708145d4"
 
 [[package]]
 name = "renderdoc-sys"