v0.8.2: cleanup + prose + structure + decomposition + budget + errors

Phase 1 — dedup + hardening (~9 items):
- Remove duplicate *skill-registry* defvar from core-skills
- Merge *backend-registry* into *probabilistic-backends*, delete backend-register
- Remove inject-stimulus alias, standardize on stimulus-inject
- Add pre-eval sandbox (skill-source-scan) blocks restricted symbols before eval
- Remove dead plist-get function; remove duplicate json-alist-to-plist export
- Fix read-framed-message whitespace DoS (4096-iteration max)
- Add *read-eval* nil to dispatcher-approvals-process read-from-string (RCE)
- Add test-op to ASDF; update .asd version 0.4.3→0.7.2

Phase 2 — prose + contracts + reorder:
- Split ROADMAP: 2623→1089 lines (TODO only), CHANGELOG: 260→1528 lines (full DONE history, 14 versions reverse chron)
- Add Contracts + Overview to 6 channel files + embedding-native + programming-standards + symbolic-scope
- Reorder 28 .org files: Contract → Test Suite → Implementation (TDD order)
- Add 7-phase inline prose to think() in core-reason
- Expand USER_MANUAL: 183→461 lines (10 new sections)

Phase 3 — decomposition + export organization:
- Decompose think() into think-assemble-prompt, think-call-llm, think-parse-response orchestrator
- Organize 188 exports into 16 grouped sections by module

Phase 4 — budget enforcement + error protocol:
- Per-session budget enforcement (SESSION_BUDGET_USD env var, budget-exhausted-p, guard in think-call-llm)
- Error condition hierarchy (6 conditions: pipeline-error, llm-error, gate-error, budget-error, protocol-error)
- Restarts in loop-process: skip-signal, use-fallback, abort-pipeline

org/security-validator.org

@@ -27,34 +27,6 @@ before they reach any cognitive stage.
 - Does NOT define the schema — that is ~core-transport.org~.
 - Does NOT validate semantic content — that is the Dispatcher and Policy.
 
-* Implementation
-
-** Package Context
-#+begin_src lisp
-(in-package :passepartout)
-#+end_src
-
-** Validation Logic
-;; REPL-VERIFIED: 2026-05-03T13:00:00
-#+begin_src lisp
-(defun validator-protocol-check (msg)
-  "Enforces structural schema compliance on protocol messages."
-  (validate-communication-protocol-schema msg))
-#+end_src
-
-** Skill Registration
-#+begin_src lisp
-(defskill :passepartout-security-validator
-  :priority 95
-  :trigger (lambda (ctx) (declare (ignore ctx)) t)
-  :deterministic (lambda (action ctx)
-                   (declare (ignore ctx))
-                   (handler-case
-                       (progn (validator-protocol-check action) action)
-                     (error (c)
-                       (list :type :LOG :payload (list :level :error :text (format nil "Protocol Violation: ~a" c)))))))
-#+end_src
-
 * Test Suite
 
 #+begin_src lisp
@@ -86,3 +58,32 @@ before they reach any cognitive stage.
     (signals error
       (validator-protocol-check msg))))
 #+end_src
+
+* Implementation
+
+** Package Context
+#+begin_src lisp
+(in-package :passepartout)
+#+end_src
+
+** Validation Logic
+;; REPL-VERIFIED: 2026-05-03T13:00:00
+#+begin_src lisp
+(defun validator-protocol-check (msg)
+  "Enforces structural schema compliance on protocol messages."
+  (validate-communication-protocol-schema msg))
+#+end_src
+
+** Skill Registration
+#+begin_src lisp
+(defskill :passepartout-security-validator
+  :priority 95
+  :trigger (lambda (ctx) (declare (ignore ctx)) t)
+  :deterministic (lambda (action ctx)
+                   (declare (ignore ctx))
+                   (handler-case
+                       (progn (validator-protocol-check action) action)
+                     (error (c)
+                       (list :type :LOG :payload (list :level :error :text (format nil "Protocol Violation: ~a" c)))))))
+#+end_src
+