fix(home-manager): ensure claude/beads plugin files are writable

Files copied from the nix store inherit read-only permissions, causing
subsequent home-manager activations to fail with "Permission denied".

Add rm -f before copy and chmod u+w after copy for all plugin files:
- humanlayer commands and agents
- local commands and skills
- micro-skills
- beads formulas

Executed-By: nixos_configs/crew/hermione
Rig: nixos_configs
Role: crew

home/roles/development/default.nix

@@ -86,12 +86,14 @@ in
         if [ -f "$file" ]; then
           filename=$(basename "$file" .md)
           dest="$HOME/.claude/commands/humanlayer:''${filename}.md"
+          rm -f "$dest" 2>/dev/null || true
 
           # Copy file and conditionally remove the "model:" line from frontmatter
           ${if cfg.allowArbitraryClaudeCodeModelSelection
             then "cp \"$file\" \"$dest\""
             else "${pkgs.gnused}/bin/sed '/^model:/d' \"$file\" > \"$dest\""
           }
+          chmod u+w "$dest" 2>/dev/null || true
         fi
       done
 
@@ -100,12 +102,14 @@ in
         if [ -f "$file" ]; then
           filename=$(basename "$file" .md)
           dest="$HOME/.claude/agents/humanlayer:''${filename}.md"
+          rm -f "$dest" 2>/dev/null || true
 
           # Copy file and conditionally remove the "model:" line from frontmatter
           ${if cfg.allowArbitraryClaudeCodeModelSelection
             then "cp \"$file\" \"$dest\""
             else "${pkgs.gnused}/bin/sed '/^model:/d' \"$file\" > \"$dest\""
           }
+          chmod u+w "$dest" 2>/dev/null || true
         fi
       done
 
@@ -120,6 +124,7 @@ in
             sleep 0.5
             cp "$file" "$dest" || echo "Warning: Failed to copy $filename.md to commands"
           fi
+          chmod u+w "$dest" 2>/dev/null || true
         fi
       done
 
@@ -134,13 +139,17 @@ in
             sleep 0.5
             cp "$file" "$dest" || echo "Warning: Failed to copy $filename.md to skills"
           fi
+          chmod u+w "$dest" 2>/dev/null || true
         fi
       done
 
       # Copy micro-skills (compact reusable knowledge referenced by formulas)
       for file in ${./skills/micro}/*.md; do
         if [ -f "$file" ]; then
-          cp "$file" "$HOME/.claude/commands/skills/$(basename "$file")"
+          dest="$HOME/.claude/commands/skills/$(basename "$file")"
+          rm -f "$dest" 2>/dev/null || true
+          cp "$file" "$dest"
+          chmod u+w "$dest" 2>/dev/null || true
         fi
       done
 
@@ -148,7 +157,10 @@ in
       mkdir -p ~/.beads/formulas
       for file in ${./formulas}/*.formula.toml; do
         if [ -f "$file" ]; then
-          cp "$file" "$HOME/.beads/formulas/$(basename "$file")"
+          dest="$HOME/.beads/formulas/$(basename "$file")"
+          rm -f "$dest" 2>/dev/null || true
+          cp "$file" "$dest"
+          chmod u+w "$dest" 2>/dev/null || true
         fi
       done