feat(tui): add file save/close commands and session save handling

- Updated command specs: added `w`, `write`, `wq`, `x`, and `session save` with proper descriptions.
- Introduced `SaveStatus` enum and helper methods for path display and buffer labeling.
- Implemented `update_paths` in `Workspace` to keep title in sync with file paths.
- Added comprehensive `save_active_code_buffer` and enhanced `close_active_code_buffer` logic, including force‑close via `!`.
- Parsed force flag from commands (e.g., `:q!`) and routed commands to new save/close workflows.
- Integrated session save subcommand with optional description generation.

crates/owlen-tui/src/commands/mod.rs

@@ -14,7 +14,15 @@ const COMMANDS: &[CommandSpec] = &[
     },
     CommandSpec {
         keyword: "q",
-        description: "Alias for quit",
+        description: "Close the active file",
+    },
+    CommandSpec {
+        keyword: "w",
+        description: "Save the active file",
+    },
+    CommandSpec {
+        keyword: "write",
+        description: "Alias for w",
     },
     CommandSpec {
         keyword: "clear",
@@ -25,12 +33,16 @@ const COMMANDS: &[CommandSpec] = &[
         description: "Alias for clear",
     },
     CommandSpec {
-        keyword: "w",
-        description: "Alias for write",
+        keyword: "save",
+        description: "Alias for w",
     },
     CommandSpec {
-        keyword: "save",
-        description: "Alias for write",
+        keyword: "wq",
+        description: "Save and close the active file",
+    },
+    CommandSpec {
+        keyword: "x",
+        description: "Alias for wq",
     },
     CommandSpec {
         keyword: "load",
@@ -68,6 +80,10 @@ const COMMANDS: &[CommandSpec] = &[
         keyword: "sessions",
         description: "List saved sessions",
     },
+    CommandSpec {
+        keyword: "session save",
+        description: "Save the current conversation",
+    },
     CommandSpec {
         keyword: "help",
         description: "Show help documentation",