refactor: update Pi agent configuration and devShell

- Switch model provider from zai/glm-5.1 to minimax/MiniMax-M2.7
- Add coding rules for Nix language and standard concerns
- Add linting tools (statix, deadnix) to devShell
- Simplify devShell configuration
- Update AGENTS.md project rules

AGENTS.md

@@ -71,6 +71,123 @@ Personal NixOS configuration managing 6 hosts (4 servers, 2 desktops) using flak
 - **master**: Bleeding edge
 - **m3ta-nixpkgs**: Custom local overlay at `path:/home/m3tam3re/p/nix/nixpkgs`
 
+## CODING RULES
+
+This project uses coding rules from the AGENTS repository (`inputs.agents`) plus project-specific conventions.
+
+### Standard Rules (AGENTS repo)
+
+| Rule | Source | Purpose |
+|------|--------|---------|
+| `languages/nix.md` | AGENTS/rules/ | Nix language conventions, flake patterns |
+| `concerns/coding-style.md` | AGENTS/rules/ | General coding principles |
+| `concerns/naming.md` | AGENTS/rules/ | Naming conventions per language |
+| `concerns/documentation.md` | AGENTS/rules/ | Documentation standards |
+| `concerns/testing.md` | AGENTS/rules/ | Testing guidelines |
+| `concerns/git-workflow.md` | AGENTS/rules/ | Commit message format, branch naming |
+| `concerns/project-structure.md` | AGENTS/rules/ | Project layout conventions |
+
+### NixOS-Config Specific Rules
+
+#### Project Structure
+
+```
+nixos-config/
+├── flake.nix              # Entry point
+├── hosts/                 # Host-specific NixOS configs
+│   ├── common/            # Shared: ports, users, base config
+│   ├── m3-atlas/          # Server with Traefik hub
+│   ├── m3-helios/         # AdGuard DNS
+│   ├── m3-ares/           # Desktop (NVIDIA)
+│   └── m3-kratos/         # Desktop (AMD)
+├── home/                   # Home-manager configs
+│   ├── common/            # Shared home config
+│   ├── features/          # Feature modules (cli, desktop, coding)
+│   └── m3tam3re/          # User-specific configs
+├── modules/               # Custom NixOS/HM modules
+├── overlays/              # Package overlays
+├── pkgs/                  # Custom packages
+└── secrets/               # Agenix encrypted secrets
+```
+
+#### Naming Conventions
+
+| Type | Convention | Example |
+|------|------------|---------|
+| Hosts | mythological-names | `m3-atlas`, `m3-helios` |
+| Files | hyphen-case | `my-service.nix` |
+| Variables | camelCase | `portHelpers`, `serviceConfig` |
+| Options | m3ta.* | `config.m3ta.ports.get` |
+| Packages | lowercase-hyphen | `hyprpaper-random` |
+
+#### Nix Module Pattern
+
+```nix
+{ config, lib, pkgs, ... }:
+with lib; let
+  cfg = config.m3ta.myModule;
+in {
+  options.m3ta.myModule = {
+    enable = mkEnableOption "my module";
+  };
+
+  config = mkIf cfg.enable {
+    # Configuration here
+  };
+}
+```
+
+#### Anti-Patterns (Never Do)
+
+| Don't | Do Instead |
+|-------|------------|
+| Hardcode ports | `config.m3ta.ports.get "service"` |
+| Skip secrets.nix update | Add keys first, then `agenix -e` |
+| Containers outside web network | `--network=web --ip=10.89.0.N` |
+| Skip Traefik for public services | Configure dynamic config |
+| Bypass extraServices flags | Use feature flags properly |
+| Use `fetchTarball` | Use flake inputs |
+| Use `with pkgs;` in modules | Explicit `pkgs.package` |
+
+### Formatting & Linting
+
+```bash
+# Format (alejandra)
+nix fmt
+
+# Lint (statix, deadnix - only in dev shell)
+nix develop
+statix check .
+deadnix .
+
+# Validate flake
+nix flake check
+```
+
+### Commit Conventions
+
+Format: `<type>: <brief description>`
+
+Types: `feat`, `fix`, `docs`, `style`, `refactor`, `chore`
+
+Examples:
+- `feat: add new host m3-hermes`
+- `fix: resolve port conflict in mem0 module`
+- `docs: update AGENTS.md with new service`
+- `style: format nix files`
+- `refactor: simplify port management`
+- `chore: update nixpkgs inputs`
+
+### Tools in Dev Shell
+
+| Tool | Purpose |
+|------|---------|
+| `alejandra` | Nix code formatter |
+| `nixd` | Nix language server |
+| `statix` | Nix linter |
+| `deadnix` | Find dead code |
+| `agenix` | Secret management |
+
 ## COMMANDS
 ```bash
 # Build/deploy specific host