remediation: backfill v0.1.0/v0.2.0 gaps (P0+P1)

- vault: add vault-get-secret/vault-set-secret wrappers
- programming-org: implement org-modify (text search-replace) and org-ast-render (AST to Org text)
- programming-literate: implement literate-block-balance-check (paren validation) and literate-tangle-sync-check (org→lisp diff)
- system-self-improve: replace stubs with surgical text editing and error diagnosis; remove dead first defskill
- system-event-orchestrator: implement orchestrator-bootstrap (scan Org files for HOOK/CRON)
- system-archivist: implement Scribe distillation (daily logs→atomic notes) and Gardener link/orphan repair
- system-memory: implement memory-inspect with type/todo/orphan statistics
- core-skills, core-context: fix path relic (skills/ → lisp/, org/)
- docs: add Token Economics section to DESIGN_DECISIONS, remediation roadmap entries

org/programming-org.org

@@ -179,21 +179,71 @@ Returns the filtered content as a string."
     nil))
 #+end_src
 
-** Placeholder for External Edits
+** Text Modification in Org Files
+Replaces text in Org files with verification. Used by =system-self-improve= for
+surgical edits.
+
 #+begin_src lisp
-(defun org-modify (filepath id changes)
-  "Placeholder for Emacs-driven modification of a specific node."
-  (declare (ignore changes))
-  (log-message "UTILS-ORG: Applying changes to ~a in ~a" id filepath)
-  t)
+(defun org-modify (filepath old-text new-text)
+  "Replaces all occurrences of OLD-TEXT with NEW-TEXT in filepath.
+Returns T if OLD-TEXT was found and replaced, nil if not found."
+  (when (not (uiop:file-exists-p filepath))
+    (log-message "UTILS-ORG: org-modify: file not found: ~a" filepath)
+    (return-from org-modify nil))
+  (let* ((content (uiop:read-file-string filepath))
+         (pos (search old-text content :test #'string=)))
+    (unless pos
+      (log-message "UTILS-ORG: org-modify: text not found in ~a" filepath)
+      (return-from org-modify nil))
+    (let ((modified (cl-ppcre:regex-replace-all
+                      (cl-ppcre:quote-meta-chars old-text)
+                      content new-text)))
+      (org-write-file filepath modified)
+      (log-message "UTILS-ORG: Modified ~a (~d chars replaced)" filepath (length old-text))
+      t)))
 #+end_src
 
-** Placeholder for AST to Org conversion
+** AST to Org text conversion
 #+begin_src lisp
-(defun org-ast-render (ast)
-  "Minimal converter from AST back to Org text (Placeholder)."
-  (declare (ignore ast))
-  "* TITLE (Placeholder)")
+(defun org-ast-render (ast &key (depth 1))
+  "Converts a plist AST node back to Org text.
+AST format: (:TYPE :HEADLINE :properties (:ID ... :TITLE ... :TAGS (...))
+              :contents (child-ast ...))"
+  (let* ((type (getf ast :TYPE))
+         (props (getf ast :properties))
+         (title (or (getf props :TITLE) "Untitled"))
+         (tags (getf props :TAGS))
+         (todo (getf props :TODO-STATE))
+         (children (getf ast :contents))
+         (raw-content (getf ast :raw-content))
+         (stars (make-string depth :initial-element #\*))
+         (output ""))
+    (unless (eq type :HEADLINE)
+      (return-from org-ast-render (or raw-content "")))
+    ;; Headline
+    (setf output (format nil "~a~@[ ~a~] ~a" stars todo title))
+    (when tags
+      (let ((tag-str (format nil "~{~a~^:~}" (mapcar (lambda (t) (string-trim '(#\:) t)) tags))))
+        (setf output (concatenate 'string output (format nil " :~a::~%" tag-str))))
+      (setf output (concatenate 'string output (string #\Newline))))
+    (unless tags
+      (setf output (concatenate 'string output (string #\Newline))))
+    ;; Property drawer
+    (setf output (concatenate 'string output ":PROPERTIES:" (string #\Newline)))
+    (loop for (k v) on props by #'cddr
+          do (unless (or (eq k :TITLE) (eq k :TAGS))
+               (setf output (concatenate 'string output
+                                         (format nil ":~a: ~a~%" k v)))))
+    (setf output (concatenate 'string output ":END:" (string #\Newline)))
+    ;; Content
+    (when raw-content
+      (setf output (concatenate 'string output raw-content (string #\Newline))))
+    ;; Children
+    (dolist (child children)
+      (when (listp child)
+        (setf output (concatenate 'string output
+                                  (org-ast-render child :depth (1+ depth))))))
+    output))
 #+end_src
 
 ** Skill Registration