add .gitignore, clean up generated files from node_modules

Remove from tracking:
- dist/ (build output, regenerated by bun run build.ts)
- node_modules/.pnpm/ (pnpm internal store, 247MB)
- node_modules/.bin/ (executable symlinks)
- node_modules/.ignored/ and .ignored_* (source-map dirs moved aside by pnpm)
- 100 pnpm-installed package symlinks (regenerated by pnpm install)

Keep in tracking:
- Private package stubs not on npm (color-diff-napi, modifiers-napi,
  @ant/claude-for-chrome-mcp, @anthropic-ai/mcpb, @anthropic-ai/sandbox-runtime)
- Source-map extracted packages not installed by pnpm (@grpc/*, @protobufjs/*, etc.)

claude-code-source/node_modules/@smithy/util-stream/dist-cjs/sdk-stream-mixin.browser.js

@@ -1,68 +0,0 @@
-"use strict";
-Object.defineProperty(exports, "__esModule", { value: true });
-exports.sdkStreamMixin = void 0;
-const fetch_http_handler_1 = require("@smithy/fetch-http-handler");
-const util_base64_1 = require("@smithy/util-base64");
-const util_hex_encoding_1 = require("@smithy/util-hex-encoding");
-const util_utf8_1 = require("@smithy/util-utf8");
-const stream_type_check_1 = require("./stream-type-check");
-const ERR_MSG_STREAM_HAS_BEEN_TRANSFORMED = "The stream has already been transformed.";
-const sdkStreamMixin = (stream) => {
-    if (!isBlobInstance(stream) && !(0, stream_type_check_1.isReadableStream)(stream)) {
-        const name = stream?.__proto__?.constructor?.name || stream;
-        throw new Error(`Unexpected stream implementation, expect Blob or ReadableStream, got ${name}`);
-    }
-    let transformed = false;
-    const transformToByteArray = async () => {
-        if (transformed) {
-            throw new Error(ERR_MSG_STREAM_HAS_BEEN_TRANSFORMED);
-        }
-        transformed = true;
-        return await (0, fetch_http_handler_1.streamCollector)(stream);
-    };
-    const blobToWebStream = (blob) => {
-        if (typeof blob.stream !== "function") {
-            throw new Error("Cannot transform payload Blob to web stream. Please make sure the Blob.stream() is polyfilled.\n" +
-                "If you are using React Native, this API is not yet supported, see: https://react-native.canny.io/feature-requests/p/fetch-streaming-body");
-        }
-        return blob.stream();
-    };
-    return Object.assign(stream, {
-        transformToByteArray: transformToByteArray,
-        transformToString: async (encoding) => {
-            const buf = await transformToByteArray();
-            if (encoding === "base64") {
-                return (0, util_base64_1.toBase64)(buf);
-            }
-            else if (encoding === "hex") {
-                return (0, util_hex_encoding_1.toHex)(buf);
-            }
-            else if (encoding === undefined || encoding === "utf8" || encoding === "utf-8") {
-                return (0, util_utf8_1.toUtf8)(buf);
-            }
-            else if (typeof TextDecoder === "function") {
-                return new TextDecoder(encoding).decode(buf);
-            }
-            else {
-                throw new Error("TextDecoder is not available, please make sure polyfill is provided.");
-            }
-        },
-        transformToWebStream: () => {
-            if (transformed) {
-                throw new Error(ERR_MSG_STREAM_HAS_BEEN_TRANSFORMED);
-            }
-            transformed = true;
-            if (isBlobInstance(stream)) {
-                return blobToWebStream(stream);
-            }
-            else if ((0, stream_type_check_1.isReadableStream)(stream)) {
-                return stream;
-            }
-            else {
-                throw new Error(`Cannot transform payload to web stream, got ${stream}`);
-            }
-        },
-    });
-};
-exports.sdkStreamMixin = sdkStreamMixin;
-const isBlobInstance = (stream) => typeof Blob === "function" && stream instanceof Blob;