build: dynamically tangle to INSTALL_DIR without copying .org files

- Updated all 150+ :tangle headers across harness/ and skills/ to use elisp (expand-file-name) to target INSTALL_DIR dynamically.
- Cleaned up environment/ directory depth by moving memory-image.lisp to state/.
- Moved test scripts to tests/ and deleted redundant chat scripts.

skills/org-skill-credentials-vault.org

@@ -33,7 +33,7 @@ Securely manage all authentication tokens required for the opencortex to operate
 The vault provides a secure lookup table in RAM, backed by the persistent Memory. Access is restricted to internal kernel requests and explicitly authorized deterministic gates.
 
 ** 2. Semantic Interfaces
-#+begin_src lisp :tangle ./org-skill-credentials-vault.lisp
+#+begin_src lisp :tangle (expand-file-name "org-skill-credentials-vault.lisp" (concat (or (getenv "INSTALL_DIR") ".") "/skills"))
 (defun vault-get-secret (provider &key type)
   "Retrieves a secret (api-key or session) for a provider.")
 
@@ -61,13 +61,13 @@ Tests in `tests/vault-tests.lisp` will verify:
 * Phase D: Build (Implementation)
 
 ** Package Context
-#+begin_src lisp :tangle ./org-skill-credentials-vault.lisp
+#+begin_src lisp :tangle (expand-file-name "org-skill-credentials-vault.lisp" (concat (or (getenv "INSTALL_DIR") ".") "/skills"))
 #+end_src
 
 ** Vault State
 We maintain an in-memory hash table for secrets, which is hydrated from and persisted to the Memory.
 
-#+begin_src lisp :tangle ./org-skill-credentials-vault.lisp
+#+begin_src lisp :tangle (expand-file-name "org-skill-credentials-vault.lisp" (concat (or (getenv "INSTALL_DIR") ".") "/skills"))
 (defvar opencortex::*vault-memory* (make-hash-table :test 'equal)
   "In-memory cache of sensitive credentials.")
 #+end_src
@@ -75,7 +75,7 @@ We maintain an in-memory hash table for secrets, which is hydrated from and pers
 ** Helper: Secret Masking
 The `vault-mask-string` function ensures that diagnostic output never contains the full plaintext of a sensitive token.
 
-#+begin_src lisp :tangle ./org-skill-credentials-vault.lisp
+#+begin_src lisp :tangle (expand-file-name "org-skill-credentials-vault.lisp" (concat (or (getenv "INSTALL_DIR") ".") "/skills"))
 (defun vault-mask-string (str)
   "Returns a masked version of a sensitive string."
   (if (and str (> (length str) 8))
@@ -86,7 +86,7 @@ The `vault-mask-string` function ensures that diagnostic output never contains t
 ** Retrieval (vault-get-secret)
 This function is the secure getter for all system secrets. It prioritizes the Vault (Memory) and falls back to environment variables for legacy compatibility.
 
-#+begin_src lisp :tangle ./org-skill-credentials-vault.lisp
+#+begin_src lisp :tangle (expand-file-name "org-skill-credentials-vault.lisp" (concat (or (getenv "INSTALL_DIR") ".") "/skills"))
 (defun vault-get-secret (provider &key (type :api-key))
   "Retrieves a credential. Type can be :api-key or :session."
   (let* ((key (format nil "~a-~a" provider type))
@@ -112,7 +112,7 @@ This function is the secure getter for all system secrets. It prioritizes the Va
 ** Persistence (vault-set-secret)
 When a secret is updated, we immediately snapshot the Memory to ensure the credential change is versioned and durable.
 
-#+begin_src lisp :tangle ./org-skill-credentials-vault.lisp
+#+begin_src lisp :tangle (expand-file-name "org-skill-credentials-vault.lisp" (concat (or (getenv "INSTALL_DIR") ".") "/skills"))
 (defun vault-set-secret (provider secret &key (type :api-key))
   "Securely stores a secret and triggers a Merkle snapshot."
   (let ((key (format nil "~a-~a" provider type)))
@@ -125,7 +125,7 @@ When a secret is updated, we immediately snapshot the Memory to ensure the crede
 ** Onboarding Logic
 Retained from the legacy Google skill, this provides the instructions for the autonomous cookie handshake.
 
-#+begin_src lisp :tangle ./org-skill-credentials-vault.lisp
+#+begin_src lisp :tangle (expand-file-name "org-skill-credentials-vault.lisp" (concat (or (getenv "INSTALL_DIR") ".") "/skills"))
 (defun vault-onboard-gemini-web ()
   "Instructions for the Autonomous Cookie Handshake."
   (harness-log "--- GEMINI WEB ONBOARDING ---")
@@ -137,7 +137,7 @@ Retained from the legacy Google skill, this provides the instructions for the au
 #+end_src
 
 ** Registration
-#+begin_src lisp :tangle ./org-skill-credentials-vault.lisp
+#+begin_src lisp :tangle (expand-file-name "org-skill-credentials-vault.lisp" (concat (or (getenv "INSTALL_DIR") ".") "/skills"))
 (progn
   (defskill :skill-credentials-vault
     :priority 200 ; High priority, foundational
@@ -153,7 +153,7 @@ Retained from the legacy Google skill, this provides the instructions for the au
 Note: Tests disabled in jail load.
 
 ** 1. Unit Tests (FiveAM)
-#+begin_src lisp :tangle ./org-skill-credentials-vault.lisp
+#+begin_src lisp :tangle (expand-file-name "org-skill-credentials-vault.lisp" (concat (or (getenv "INSTALL_DIR") ".") "/skills"))
 #|
 (defpackage :opencortex-vault-tests
   (:use :cl :fiveam :opencortex))