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/node-config-provider/dist-cjs/index.js

@@ -1,62 +0,0 @@
-'use strict';
-
-var propertyProvider = require('@smithy/property-provider');
-var sharedIniFileLoader = require('@smithy/shared-ini-file-loader');
-
-function getSelectorName(functionString) {
-    try {
-        const constants = new Set(Array.from(functionString.match(/([A-Z_]){3,}/g) ?? []));
-        constants.delete("CONFIG");
-        constants.delete("CONFIG_PREFIX_SEPARATOR");
-        constants.delete("ENV");
-        return [...constants].join(", ");
-    }
-    catch (e) {
-        return functionString;
-    }
-}
-
-const fromEnv = (envVarSelector, options) => async () => {
-    try {
-        const config = envVarSelector(process.env, options);
-        if (config === undefined) {
-            throw new Error();
-        }
-        return config;
-    }
-    catch (e) {
-        throw new propertyProvider.CredentialsProviderError(e.message || `Not found in ENV: ${getSelectorName(envVarSelector.toString())}`, { logger: options?.logger });
-    }
-};
-
-const fromSharedConfigFiles = (configSelector, { preferredFile = "config", ...init } = {}) => async () => {
-    const profile = sharedIniFileLoader.getProfileName(init);
-    const { configFile, credentialsFile } = await sharedIniFileLoader.loadSharedConfigFiles(init);
-    const profileFromCredentials = credentialsFile[profile] || {};
-    const profileFromConfig = configFile[profile] || {};
-    const mergedProfile = preferredFile === "config"
-        ? { ...profileFromCredentials, ...profileFromConfig }
-        : { ...profileFromConfig, ...profileFromCredentials };
-    try {
-        const cfgFile = preferredFile === "config" ? configFile : credentialsFile;
-        const configValue = configSelector(mergedProfile, cfgFile);
-        if (configValue === undefined) {
-            throw new Error();
-        }
-        return configValue;
-    }
-    catch (e) {
-        throw new propertyProvider.CredentialsProviderError(e.message || `Not found in config files w/ profile [${profile}]: ${getSelectorName(configSelector.toString())}`, { logger: init.logger });
-    }
-};
-
-const isFunction = (func) => typeof func === "function";
-const fromStatic = (defaultValue) => isFunction(defaultValue) ? async () => await defaultValue() : propertyProvider.fromStatic(defaultValue);
-
-const loadConfig = ({ environmentVariableSelector, configFileSelector, default: defaultValue }, configuration = {}) => {
-    const { signingName, logger } = configuration;
-    const envOptions = { signingName, logger };
-    return propertyProvider.memoize(propertyProvider.chain(fromEnv(environmentVariableSelector, envOptions), fromSharedConfigFiles(configFileSelector, configuration), fromStatic(defaultValue)));
-};
-
-exports.loadConfig = loadConfig;