feat(lsp): add Python language server support

- Add pyright-langserver for Python LSP support
- Add environment variable overrides for Python LSP configuration
- Install git in Docker image (required for gopls dependency resolution)
- Optimize Go binary build with -s -w linker flags for smaller image
- Add GOPROXY configuration for faster dependency downloads
- Update Node.js installation method with GPG key verification
- Add entrypoint script to auto-create go.mod in workspace
- Add /app/logs volume for log persistence

backend/cmd/server/main.go

@@ -735,6 +735,12 @@ func defaultLanguageServers() []completion.LanguageServerSpec {
 			Command:    "typescript-language-server",
 			Args:       []string{"--stdio"},
 		},
+		{
+			Language:   "python",
+			LanguageID: "python",
+			Command:    "pyright-langserver",
+			Args:       []string{"--stdio"},
+		},
 	}
 }
 
@@ -754,6 +760,7 @@ func applyLanguageServerEnvOverrides(servers []completion.LanguageServerSpec) []
 	overridden = applySingleLanguageServerEnv(overridden, "go", "go", "GO_LSP_COMMAND", "GO_LSP_ARGS", "gopls", "")
 	overridden = applySingleLanguageServerEnv(overridden, "javascript", "javascript", "JAVASCRIPT_LSP_COMMAND", "JAVASCRIPT_LSP_ARGS", "typescript-language-server", "--stdio")
 	overridden = applySingleLanguageServerEnv(overridden, "typescript", "typescript", "TYPESCRIPT_LSP_COMMAND", "TYPESCRIPT_LSP_ARGS", "typescript-language-server", "--stdio")
+	overridden = applySingleLanguageServerEnv(overridden, "python", "python", "PYTHON_LSP_COMMAND", "PYTHON_LSP_ARGS", "pyright-langserver", "--stdio")
 	return overridden
 }