Set temperature=1.0, top_k=64, top_p=0.95 for all profiles (Google recommended for gemma4) ...

Also fixes discuss profile memory tools: use combined "memory" tool name, not nonexistent split variants.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Add per-phase planning flags and planning_mandatory ...

- planning_mandatory: disables DIRECT shortcut, forces all phases to run
- planning_phase1_enabled / phase2_enabled / phase3_enabled: per-phase toggles
- planning_phase2_enabled replaces planning_reflect_enabled (migrated in loader with backward compat)
- Migrate all profile configs; rewrite docs/profiles.md as full config reference

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Add Ollama multi-server fallback with in-memory blacklisting ...

- New FallbackOllamaBackend (navi/llm/fallback.py): tries servers and
  models in priority order; on LLMConnectionError blacklists the server
  for the process lifetime, on LLMModelNotFoundError blacklists the
  (server, model) pair — eliminates latency from repeated failed probes
- OllamaBackend now raises typed LLMConnectionError / LLMModelNotFoundError
  instead of bare LLMBackendError; accepts list[str] | str | None for model
- AgentProfile.model changed from str to list[str] (str auto-normalised);
  all profiles updated to ["gemma4:31b-cloud", "gemma4:26b-a4b-it-q4_K_M"]
- New config field OLLAMA_BACKENDS_FILE: path to [{host, api_key?}] JSON;
  when set, registry creates FallbackOllamaBackend instead of OllamaBackend
- ollama_backends.json template added (gitignored — contains API key)
- current_model ContextVar type widened to list[str] | str | None

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Use gemma4 cloud model by default

Support Ollama Cloud API key

Agent improvements: mandatory planning, tool cleanup, smart_edit fixes ...

- Planning now mandatory on first message of every session (force_plan)
- RESOURCES, COMMITMENTS, ATOMICITY fields added to planning phase 1
- Todo auto-injected at iteration 0 so model tracks steps immediately
- Execution trigger injected after plan to prevent model treating plan as response
- Split developer profile: tool_developer (Navi tools) vs developer (general code)
- Simplified persona.txt: trimmed redundant content now handled by mechanics
- AIHelper.ask(): 120s timeout via asyncio.wait_for to prevent smart_edit hangs
- filesystem._smart_edit(): atomic write via temp file + os.replace()
- Removed 5 junk user tools (game project artifacts, trivial utilities)
- Removed instagram tools (to be rewritten); cleaned enabled.json

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>