tools: add repl-block, check-tangle; move existing tools into memex

New tools (projects/<tool>/ — standalone, git-committed):
- repl-block: extract and pipe lisp blocks from org files to the REPL
- check-tangle: tangle + compile in one step, reports errors

Existing tools moved from ~/.opencode/bin/ into memex (survives reinstalls):
- repl, tangle, org-eval, verify-repl

AGENTS.md updated:
- Tool reference table with all 7 tools
- Package reference table for passepartout and cl-tty
- Updated tangle command to use project-local tools

.opencode/commands/ added: check-parens, repl-block, check-tangle commands

projects/org-eval-tool/org-eval

@@ -0,0 +1,43 @@
+#!/usr/bin/env bash
+# Evaluate an org src block using Emacs batch mode
+# Usage: org-eval <org-file> [block-index]
+# If block-index is not provided, evaluates all blocks
+
+set -e
+
+if [ $# -lt 1 ]; then
+    echo "Usage: org-eval <org-file> [block-index]"
+    echo "  Evaluates src blocks in the org file"
+    echo "  If block-index is omitted, evaluates ALL blocks"
+    exit 1
+fi
+
+ORG_FILE="$1"
+BLOCK_INDEX="${2:-}"
+
+if [ ! -f "$ORG_FILE" ]; then
+    echo "Error: File not found: $ORG_FILE"
+    exit 1
+fi
+
+echo "Evaluating: $ORG_FILE"
+
+if [ -n "$BLOCK_INDEX" ]; then
+    # Evaluate specific block
+    emacs --batch \
+        --load org \
+        --eval "(setq org-confirm-babel-evaluate nil)" \
+        --eval "(with-current-buffer (find-file-noselect \"$ORG_FILE\") \
+                 (goto-char (point-min)) \
+                 (dotimes (_ $BLOCK_INDEX) \
+                   (org-babel-next-src-block)) \
+                 (org-babel-execute-src-block))"
+else
+    # Evaluate all blocks
+    emacs --batch \
+        --load org \
+        --eval "(setq org-confirm-babel-evaluate nil)" \
+        --eval "(org-babel-execute-buffer)"
+fi
+
+echo "Done."