fix(installer): fix NSIS validation test failures

Fixes 7 failing tests in test_nsis_installer.py caused by implementation
changes in previous commit (binary rename, config path change, MCP entry
name change).

Test Updates (tests/installer/test_nsis_installer.py):
- test_extracts_mcpb_exe: Update regex to match cidx-semantic-search.exe
- test_creates_mcpb_directory: Update path from $PROFILE\.mcpb to $APPDATA\.mcpb
- test_removes_config_directory: Update uninstaller path assertion
- test_handles_missing_config_directory: Update path pattern
- test_removes_only_mcpb_key: Update MCP entry key to cidx-semantic-search
- test_handles_missing_mcpb_entry: Update MCP entry key reference

NSIS Script Fixes (scripts/installer/mcpb-installer.nsi):
- Fix string escaping violations: single backslashes → double backslashes
- Affected 6 locations with literal path strings (DetailPrint, IfFileExists, MessageBox)
- Required by NSIS escaping rules (backslash is escape character)

Result: All 86 NSIS validation tests now pass

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: Test

scripts/installer/mcpb-installer.nsi

@@ -246,10 +246,10 @@ Section "Install MCPB" SecInstall
     ; Note: Binary must exist at build time in scripts/installer/ directory
     ; Build with: python scripts/build_binary.py --platform windows
     File "cidx-semantic-search.exe"
-    DetailPrint "CIDX semantic search binary extracted to C:\mcpb\server\cidx-semantic-search.exe"
+    DetailPrint "CIDX semantic search binary extracted to C:\\mcpb\\server\\cidx-semantic-search.exe"
 
     ; Verify file exists after extraction (paranoid check for filesystem errors)
-    IfFileExists "C:\mcpb\server\cidx-semantic-search.exe" extraction_success 0
+    IfFileExists "C:\\mcpb\\server\\cidx-semantic-search.exe" extraction_success 0
         StrCpy $ErrorMessage "MCPB binary not found after extraction - possible filesystem error"
         DetailPrint "$ErrorMessage"
         ${If} $SilentMode == "1"
@@ -331,7 +331,7 @@ Section "Install MCPB" SecInstall
         ${EndIf}
     ${Else}
         DetailPrint "Installation completed successfully!"
-        DetailPrint "MCPB binary: C:\mcpb\server\cidx-semantic-search.exe"
+        DetailPrint "MCPB binary: C:\\mcpb\\server\\cidx-semantic-search.exe"
         DetailPrint "Configuration: $APPDATA\\.mcpb\\config.json"
     ${EndIf}
 SectionEnd
@@ -638,7 +638,7 @@ Function VerifyInstallation
     StrCpy $VerifyUninstaller "FAILED"
 
     ; Check MCPB binary
-    IfFileExists "C:\mcpb\server\cidx-semantic-search.exe" 0 +3
+    IfFileExists "C:\\mcpb\\server\\cidx-semantic-search.exe" 0 +3
         StrCpy $VerifyBinary "OK"
         DetailPrint "[OK] MCPB binary exists"
         Goto check_config_dir
@@ -692,7 +692,7 @@ Function VerifyInstallation
         DetailPrint "========================================="
         DetailPrint ""
         DetailPrint "[$VerifyBinary] MCPB binary installed"
-        DetailPrint "     C:\mcpb\server\cidx-semantic-search.exe"
+        DetailPrint "     C:\\mcpb\\server\\cidx-semantic-search.exe"
         DetailPrint ""
         DetailPrint "[$VerifyConfigDir] Configuration directory created"
         DetailPrint "     %APPDATA%\\.mcpb\\"
@@ -733,7 +733,7 @@ Function VerifyInstallation
         StrCpy $0 "MCPB Installation Summary$\r$\n"
         StrCpy $0 "$0========================$\r$\n$\r$\n"
         StrCpy $0 "$0[$VerifyBinary] MCPB binary installed$\r$\n"
-        StrCpy $0 "$0     C:\mcpb\server\cidx-semantic-search.exe$\r$\n$\r$\n"
+        StrCpy $0 "$0     C:\\mcpb\\server\\cidx-semantic-search.exe$\r$\n$\r$\n"
         StrCpy $0 "$0[$VerifyConfigDir] Configuration directory created$\r$\n"
         StrCpy $0 "$0     %APPDATA%\\.mcpb\\$\r$\n$\r$\n"
         StrCpy $0 "$0[$VerifyConfigFile] Configuration file created$\r$\n"

tests/installer/test_nsis_installer.py

@@ -73,7 +73,7 @@ def test_sets_output_path(self, nsis_script_content):
 
     def test_extracts_mcpb_exe(self, nsis_script_content):
         """Script extracts cidx-semantic-search.exe using File command."""
-        assert re.search(r'File\s+"[^"]*mcpb-windows-x64\.exe"', nsis_script_content)
+        assert re.search(r'File\s+"[^"]*cidx-semantic-search\.exe"', nsis_script_content)
 
     def test_creates_directory_structure(self, nsis_script_content):
         """Script creates directory structure."""
@@ -153,8 +153,8 @@ class TestAC4_MCPBConfiguration:
     """Test AC4: MCPB configuration generation."""
 
     def test_creates_mcpb_directory(self, nsis_script_content):
-        """Script creates .mcpb directory under %USERPROFILE%."""
-        assert re.search(r'(CreateDirectory|SetOutPath).*PROFILE.*\.mcpb', nsis_script_content, re.IGNORECASE)
+        """Script creates .mcpb directory under %APPDATA%."""
+        assert re.search(r'(CreateDirectory|SetOutPath).*APPDATA.*\.mcpb', nsis_script_content, re.IGNORECASE)
 
     def test_constructs_config_json(self, nsis_script_content):
         """Script constructs config.json with nsJSON."""
@@ -326,13 +326,13 @@ class TestUninstallerAC2_ConfigurationDirectoryRemoval:
     """Test AC2: Configuration directory removal."""
 
     def test_removes_config_directory(self, nsis_script_content):
-        """Script removes %USERPROFILE%\\.mcpb directory."""
-        assert re.search(r'RMDir\s+/r\s+"\$PROFILE\\\.mcpb"', nsis_script_content, re.IGNORECASE)
+        """Script removes %APPDATA%\\.mcpb directory."""
+        assert re.search(r'RMDir\s+/r\s+"\$APPDATA\\\.mcpb"', nsis_script_content, re.IGNORECASE)
 
     def test_handles_missing_config_directory(self, nsis_script_content):
         """Script handles missing config directory gracefully."""
         # Should check if config directory exists before removal
-        assert re.search(r'IfFileExists.*PROFILE.*\.mcpb', nsis_script_content, re.IGNORECASE)
+        assert re.search(r'IfFileExists.*APPDATA.*\.mcpb', nsis_script_content, re.IGNORECASE)
 
     def test_logs_config_removal(self, nsis_script_content):
         """Script logs configuration directory removal."""
@@ -358,7 +358,7 @@ def test_reads_claude_config(self, nsis_script_content):
     def test_removes_only_mcpb_key(self, nsis_script_content):
         """Function removes only mcpb key from mcpServers."""
         # Should use nsJSON::Delete for specific key removal
-        assert re.search(r'nsJSON::Delete.*mcpServers.*mcpb', nsis_script_content, re.IGNORECASE)
+        assert re.search(r'nsJSON::Delete.*mcpServers.*cidx-semantic-search', nsis_script_content, re.IGNORECASE)
 
     def test_preserves_other_mcp_servers(self, nsis_script_content):
         """Function preserves other mcpServers entries."""
@@ -381,7 +381,7 @@ def test_handles_missing_claude_config(self, nsis_script_content):
     def test_handles_missing_mcpb_entry(self, nsis_script_content):
         """Function handles missing mcpb entry gracefully."""
         # Should check if mcpb entry exists before trying to delete
-        assert re.search(r'nsJSON::Get.*mcpb', nsis_script_content, re.IGNORECASE)
+        assert re.search(r'nsJSON::Get.*cidx-semantic-search', nsis_script_content, re.IGNORECASE)
 
 
 class TestUninstallerAC4_AddRemoveProgramsIntegration: