feat: stats and achievements (#45)

### Explanation

_No response_

### Issue

Closes #39

### Attestations

- [ ] I have read and agree to the [Code of Conduct](https://docs.nhcarrigan.com/community/coc/)
- [ ] I have read and agree to the [Community Guidelines](https://docs.nhcarrigan.com/community/guide/).
- [ ] My contribution complies with the [Contributor Covenant](https://docs.nhcarrigan.com/dev/covenant/).

### Dependencies

- [ ] I have pinned the dependencies to a specific patch version.

### Style

- [ ] I have run the linter and resolved any errors.
- [ ] My pull request uses an appropriate title, matching the conventional commit standards.
- [ ] My scope of feat/fix/chore/etc. correctly matches the nature of changes in my pull request.

### Tests

- [ ] My contribution adds new code, and I have added tests to cover it.
- [ ] My contribution modifies existing code, and I have updated the tests to reflect these changes.
- [ ] All new and existing tests pass locally with my changes.
- [ ] Code coverage remains at or above the configured threshold.

### Documentation

_No response_

### Versioning

_No response_

Reviewed-on: #45
Co-authored-by: Naomi Carrigan <commits@nhcarrigan.com>
Co-committed-by: Naomi Carrigan <commits@nhcarrigan.com>

src/app.css

@@ -10,7 +10,14 @@
   --accent-secondary: #ff6b9d;
   --text-primary: #ffffff;
   --text-secondary: #a0a0a0;
+  --text-tertiary: #6b7280;
   --border-color: #2a2a4a;
+
+  /* Terminal specific colors */
+  --terminal-user: #22d3ee;
+  --terminal-tool: #c084fc;
+  --terminal-tool-name: #ddd6fe;
+  --terminal-error: #f87171;
 }
 
 [data-theme="light"] {
@@ -22,7 +29,14 @@
   --accent-secondary: #ff6b9d;
   --text-primary: #1a1a2e;
   --text-secondary: #5a5a7a;
+  --text-tertiary: #9ca3af;
   --border-color: #d0d0e0;
+
+  /* Terminal specific colors */
+  --terminal-user: #0891b2;
+  --terminal-tool: #7c3aed;
+  --terminal-tool-name: #8b5cf6;
+  --terminal-error: #dc2626;
 }
 
 html,