chore(license): relicense panll metadata AGPL-3.0-or-later → MPL-2.0

panll is an owner-sole repo; estate policy is MPL-2.0 (PMPL is sanctioned only
in palimpsest-license/palimpsest-plasma/consent-aware-http). origin/main carried
AGPL-3.0-or-later, which is drift. Converts repo-licence declarations only:

- LICENSE: AGPL-3.0-or-later → MPL-2.0 (full text)
- Cargo.toml, tools/pcc/Cargo.toml: license field → MPL-2.0
- deno.json, clade-portal/deno.json: license field → MPL-2.0

Source-file SPDX headers (18 AGPL-declared files under migration/ and
src/ui/tea/) and PMPL header drift are deliberately NOT touched here — held for
explicit review. Resolves part of #75.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: hyperpolymath

Cargo.toml

@@ -17,7 +17,7 @@ version = "0.2.0"
 description = "PanLL eNSAID - Environment for NeSy-Agentic Integrated Development (Gossamer backend)"
 authors = ["Jonathan D.A. Jewell <j.d.a.jewell@open.ac.uk>"]
 edition = "2021"
-license = "AGPL-3.0-or-later"
+license = "MPL-2.0"
 repository = "https://github.com/hyperpolymath/panll"
 
 # Testable logic library — GTK/WebKit-free. `cargo test --lib` runs without