Pavel/add tabnine cli support (#1503)

* feat: add Tabnine CLI agent support

Tabnine CLI is a Gemini fork that uses TOML commands with the
.tabnine/agent/ directory structure and TABNINE.md context files.

Changes:
- Add 'tabnine' to AGENT_CONFIG in __init__.py
- Update release scripts (bash + PowerShell) for TOML command generation
- Update agent context scripts (bash + PowerShell)
- Add to GitHub release packages
- Update README.md and AGENTS.md documentation
- Bump version to 0.1.14
- Add 8 new tests for cross-file consistency

* fix: add missing generic to agent-context script usage string

tests/test_ai_skills.py

@@ -147,6 +147,11 @@ class TestGetSkillsDir:
         result = _get_skills_dir(project_dir, "gemini")
         assert result == project_dir / ".gemini" / "skills"
 
+    def test_tabnine_skills_dir(self, project_dir):
+        """Tabnine should use .tabnine/agent/skills/."""
+        result = _get_skills_dir(project_dir, "tabnine")
+        assert result == project_dir / ".tabnine" / "agent" / "skills"
+
     def test_copilot_skills_dir(self, project_dir):
         """Copilot should use .github/skills/."""
         result = _get_skills_dir(project_dir, "copilot")