Make license declarations consistently MIT

The source headers, LICENSE files, and license metadata had drifted
apart. Align the entire project to MIT:

- Convert every source-file header to the MIT text across all comment
  styles (Go, TS, TSX, JS, MJS, SQL, CSS, GraphQL, shell), including
  SPDX-License-Identifier tags
- Set the root and cookie-banner LICENSE files to the MIT text with a
  "MIT License" title line
- Switch the package.json license fields, Docker image label, and
  cookie-banner README to MIT
- Update docs and the genmodels header generator accordingly
- Normalize copyright lines to a single format
  (Copyright (c) <year(s)> Probo Inc <hello@probo.com>.): unify the
  hello@getprobo.com and hello@probo.inc emails to hello@probo.com and
  the comma-separated years to a hyphenated range

Genuine third-party references are intentionally left untouched: the
Lucide icon attributions (Lucide is ISC) and the trivy dependency
license allowlist.

Signed-off-by: Sacha Al Himdani <sacha@probo.com>

AGENTS.md

@@ -37,7 +37,7 @@ Detailed guides for specific subsystems live in `contrib/claude/`:
 - [`contrib/claude/prompt-style.md`](contrib/claude/prompt-style.md) — Agent prompt template structure (role/task/instructions XML style)
 - [`contrib/claude/prompt-style.md`](contrib/claude/prompt-style.md) — Agent prompt template structure (role/task/instructions XML style)
 - [`contrib/claude/commit.md`](contrib/claude/commit.md) — Commit message conventions
-- [`contrib/claude/license.md`](contrib/claude/license.md) — ISC license header (all file types)
+- [`contrib/claude/license.md`](contrib/claude/license.md) — MIT license header (all file types)
 - [`contrib/claude/release/README.md`](contrib/claude/release/README.md) — Release process (per-track version bump, changelog, tag, push)
 - [`contrib/claude/sandbox.md`](contrib/claude/sandbox.md) — Lima sandbox environments (create, manage, access services)
 - [`contrib/claude/n8n.md`](contrib/claude/n8n.md) — n8n community node (resources, operations, GraphQL helpers)