test: Added unit tests for the rag, completions and prompt, macros, vault, and functions/tool usage

docs/testing/plans/14-macros.md

@@ -1,14 +1,24 @@
 # Test Plan: Macros
 
 ## Behaviors to test
-- [ ] Macro loaded from YAML file
-- [ ] Macro steps executed sequentially
-- [ ] Each step runs through run_repl_command
-- [ ] Variable interpolation in macro steps
-- [ ] Built-in macros installed on first run
-- [ ] macro_execute creates isolated RequestContext
-- [ ] Macro context inherits tool scope from parent
-- [ ] Macro context has macro_flag set
+- [ ] Macro loaded from YAML file (requires filesystem)
+- [ ] Macro steps executed sequentially (requires async + RequestContext)
+- [ ] Each step runs through run_repl_command (requires async)
+- [x] Variable interpolation in macro steps
+- [ ] Built-in macros installed on first run (requires filesystem)
+- [ ] macro_execute creates isolated RequestContext (requires async)
+- [ ] Macro context inherits tool scope from parent (requires async)
+- [ ] Macro context has macro_flag set (requires async)
+
+## Additional behaviors tested
+
+- [x] resolve_variables: no variables, required provided, required missing errors
+- [x] resolve_variables: default used, default overridden
+- [x] resolve_variables: rest captures remaining args, rest with default
+- [x] resolve_variables: multiple variables mixed
+- [x] usage: no variables, required, optional, rest, rest+default, mixed
+- [x] interpolate_command: single, multiple, no vars, missing var passthrough
+- [x] YAML deserialization: with variables, with defaults, no variables
 
 ## Old code reference
 - `src/config/macros.rs` — macro_execute, Macro struct