feat(v3.12.0): media pipeline, AI image generation, capability probe, companion v2.9.0

Three-month batch sync from internal repo (~80 commits) covering Tracks F.5a, F.7e, F.8, F.17, F.18, F.X.

WordPress media pipeline
- Pillow-based optimization, AI image generation (OpenAI / Stability / Replicate / Google Nano Banana / OpenRouter), chunked + resumable uploads, bulk delete/reassign, idempotent retries.

Capability discovery (F.7e)
- Per-site credential probe + adapters for WordPress / WooCommerce / Gitea, tier-fit unions granted ∪ roles, capability badge UI with HTMX partial re-check, install hint in every companion-unreachable error.

Companion plugin overhaul
- Renamed wordpress-plugin/airano-mcp-seo-bridge → wordpress-plugin/airano-mcp-bridge.
- Eight new endpoints: /capabilities, /bulk-meta, /export, /cache-purge, /transient-flush, /site-health, /audit-hook, /upload-and-attach.
- wp.org Plugin Check pass: i18n, WP_Filesystem, scheme allowlist on audit-hook URL.

Other
- Gitea ergonomics (F.17): batch files, tree, search, compare, releases, fork.
- Opportunistic bcrypt upgrade for legacy SHA-256 admin keys (F.8).
- n8n refactor: structured errors, capability probe, missing tools backfilled.
- Idempotency-Key dedup for AI media upload retries; WP client fast-fails on unreachable sites.

Docs
- README + CLAUDE.md drop the fixed "633 tools" claim. The total grows with each release; per-plugin approximations + dashboard-surfaced counts replace it.
- Tools/Tests badges removed in favour of "Plugins: 10".

Deployment
- PyPI mirror chain, optional BUILD_HTTP_PROXY, Alpine→Yandex apk mirror, Debian-slim Plan-B Dockerfile, mirror.gcr.io variant.

CI
- Black + Ruff clean on Python 3.12; pytest tests/ green.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

plugins/ai_image/providers/base.py

@@ -0,0 +1,72 @@
+"""Base types for AI image providers (F.5a.4).
+
+Each concrete provider subclasses :class:`BaseImageProvider` and implements
+``generate()``. Providers return raw image bytes + MIME so the caller (e.g.
+the WordPress upload pipeline) can reuse the existing raw-upload path.
+"""
+
+from __future__ import annotations
+
+from abc import ABC, abstractmethod
+from dataclasses import dataclass, field
+from typing import Any
+
+
+class ProviderError(Exception):
+    """Stable-coded error for provider failures.
+
+    Codes follow the F.5a error taxonomy (``PROVIDER_QUOTA``,
+    ``PROVIDER_AUTH``, ``PROVIDER_BAD_REQUEST``, ``PROVIDER_UNAVAILABLE``,
+    ``PROVIDER_TIMEOUT``). ``details`` is JSON-serialisable.
+    """
+
+    def __init__(self, code: str, message: str, details: dict[str, Any] | None = None):
+        super().__init__(message)
+        self.code = code
+        self.message = message
+        self.details = details or {}
+
+    def to_dict(self) -> dict[str, Any]:
+        return {"error_code": self.code, "message": self.message, "details": self.details}
+
+
+@dataclass
+class GenerationRequest:
+    """Normalised generation parameters.
+
+    Not every provider uses every field — unknown fields are ignored.
+    """
+
+    prompt: str
+    size: str = "1024x1024"
+    quality: str = "standard"
+    model: str | None = None
+    negative_prompt: str | None = None
+    extras: dict[str, Any] = field(default_factory=dict)
+
+
+@dataclass
+class GenerationResult:
+    """Raw bytes + metadata returned by a provider."""
+
+    data: bytes
+    mime: str
+    filename: str
+    meta: dict[str, Any] = field(default_factory=dict)
+    cost_usd: float | None = None
+
+
+class BaseImageProvider(ABC):
+    """Abstract provider: turns ``(api_key, request)`` into image bytes."""
+
+    name: str = "base"
+
+    @abstractmethod
+    async def generate(self, api_key: str, request: GenerationRequest) -> GenerationResult:
+        """Call the provider API and return image bytes + metadata.
+
+        Implementations should raise :class:`ProviderError` with a stable
+        code for predictable client handling. Network retries for transient
+        failures (429 / 5xx) should happen inside the implementation.
+        """
+        raise NotImplementedError