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/@aws-sdk/client-cognito-identity/dist-cjs/auth/httpAuthSchemeProvider.js

@@ -1,68 +0,0 @@
-"use strict";
-Object.defineProperty(exports, "__esModule", { value: true });
-exports.resolveHttpAuthSchemeConfig = exports.defaultCognitoIdentityHttpAuthSchemeProvider = exports.defaultCognitoIdentityHttpAuthSchemeParametersProvider = void 0;
-const core_1 = require("@aws-sdk/core");
-const util_middleware_1 = require("@smithy/util-middleware");
-const defaultCognitoIdentityHttpAuthSchemeParametersProvider = async (config, context, input) => {
-    return {
-        operation: (0, util_middleware_1.getSmithyContext)(context).operation,
-        region: (await (0, util_middleware_1.normalizeProvider)(config.region)()) ||
-            (() => {
-                throw new Error("expected `region` to be configured for `aws.auth#sigv4`");
-            })(),
-    };
-};
-exports.defaultCognitoIdentityHttpAuthSchemeParametersProvider = defaultCognitoIdentityHttpAuthSchemeParametersProvider;
-function createAwsAuthSigv4HttpAuthOption(authParameters) {
-    return {
-        schemeId: "aws.auth#sigv4",
-        signingProperties: {
-            name: "cognito-identity",
-            region: authParameters.region,
-        },
-        propertiesExtractor: (config, context) => ({
-            signingProperties: {
-                config,
-                context,
-            },
-        }),
-    };
-}
-function createSmithyApiNoAuthHttpAuthOption(authParameters) {
-    return {
-        schemeId: "smithy.api#noAuth",
-    };
-}
-const defaultCognitoIdentityHttpAuthSchemeProvider = (authParameters) => {
-    const options = [];
-    switch (authParameters.operation) {
-        case "GetCredentialsForIdentity": {
-            options.push(createSmithyApiNoAuthHttpAuthOption(authParameters));
-            break;
-        }
-        case "GetId": {
-            options.push(createSmithyApiNoAuthHttpAuthOption(authParameters));
-            break;
-        }
-        case "GetOpenIdToken": {
-            options.push(createSmithyApiNoAuthHttpAuthOption(authParameters));
-            break;
-        }
-        case "UnlinkIdentity": {
-            options.push(createSmithyApiNoAuthHttpAuthOption(authParameters));
-            break;
-        }
-        default: {
-            options.push(createAwsAuthSigv4HttpAuthOption(authParameters));
-        }
-    }
-    return options;
-};
-exports.defaultCognitoIdentityHttpAuthSchemeProvider = defaultCognitoIdentityHttpAuthSchemeProvider;
-const resolveHttpAuthSchemeConfig = (config) => {
-    const config_0 = (0, core_1.resolveAwsSdkSigV4Config)(config);
-    return Object.assign(config_0, {
-        authSchemePreference: (0, util_middleware_1.normalizeProvider)(config.authSchemePreference ?? []),
-    });
-};
-exports.resolveHttpAuthSchemeConfig = resolveHttpAuthSchemeConfig;