fix: sanitize tool_use.id to comply with Claude API regex ^[a-zA-Z0-9_-]+$

Add util.SanitizeClaudeToolID() to replace non-conforming characters in
tool_use.id fields across all five response translators (gemini, codex,
openai, antigravity, gemini-cli).

Upstream tool names may contain dots or other special characters
(e.g. "fs.readFile") that violate Claude's ID validation regex.
The sanitizer replaces such characters with underscores and provides
a generated fallback for empty IDs.

Fixes #1872, Fixes #1849

Made-with: Cursor

internal/translator/gemini/claude/gemini_claude_response.go

@@ -224,7 +224,7 @@ func ConvertGeminiResponseToClaude(_ context.Context, _ string, originalRequestR
 
 				// Create the tool use block with unique ID and function details
 				data := fmt.Sprintf(`{"type":"content_block_start","index":%d,"content_block":{"type":"tool_use","id":"","name":"","input":{}}}`, (*param).(*Params).ResponseIndex)
-				data, _ = sjson.Set(data, "content_block.id", fmt.Sprintf("%s-%d", upstreamToolName, atomic.AddUint64(&toolUseIDCounter, 1)))
+				data, _ = sjson.Set(data, "content_block.id", util.SanitizeClaudeToolID(fmt.Sprintf("%s-%d", upstreamToolName, atomic.AddUint64(&toolUseIDCounter, 1))))
 				data, _ = sjson.Set(data, "content_block.name", clientToolName)
 				output = output + fmt.Sprintf("data: %s\n\n\n", data)
 
@@ -343,7 +343,7 @@ func ConvertGeminiResponseToClaudeNonStream(_ context.Context, _ string, origina
 				clientToolName := util.MapToolName(toolNameMap, upstreamToolName)
 				toolIDCounter++
 				toolBlock := `{"type":"tool_use","id":"","name":"","input":{}}`
-				toolBlock, _ = sjson.Set(toolBlock, "id", fmt.Sprintf("%s-%d", upstreamToolName, toolIDCounter))
+				toolBlock, _ = sjson.Set(toolBlock, "id", util.SanitizeClaudeToolID(fmt.Sprintf("%s-%d", upstreamToolName, toolIDCounter)))
 				toolBlock, _ = sjson.Set(toolBlock, "name", clientToolName)
 				inputRaw := "{}"
 				if args := functionCall.Get("args"); args.Exists() && gjson.Valid(args.Raw) && args.IsObject() {