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/credential-provider-http/dist-cjs/fromHttp/checkUrl.js

@@ -1,46 +0,0 @@
-"use strict";
-Object.defineProperty(exports, "__esModule", { value: true });
-exports.checkUrl = void 0;
-const property_provider_1 = require("@smithy/property-provider");
-const LOOPBACK_CIDR_IPv4 = "127.0.0.0/8";
-const LOOPBACK_CIDR_IPv6 = "::1/128";
-const ECS_CONTAINER_HOST = "169.254.170.2";
-const EKS_CONTAINER_HOST_IPv4 = "169.254.170.23";
-const EKS_CONTAINER_HOST_IPv6 = "[fd00:ec2::23]";
-const checkUrl = (url, logger) => {
-    if (url.protocol === "https:") {
-        return;
-    }
-    if (url.hostname === ECS_CONTAINER_HOST ||
-        url.hostname === EKS_CONTAINER_HOST_IPv4 ||
-        url.hostname === EKS_CONTAINER_HOST_IPv6) {
-        return;
-    }
-    if (url.hostname.includes("[")) {
-        if (url.hostname === "[::1]" || url.hostname === "[0000:0000:0000:0000:0000:0000:0000:0001]") {
-            return;
-        }
-    }
-    else {
-        if (url.hostname === "localhost") {
-            return;
-        }
-        const ipComponents = url.hostname.split(".");
-        const inRange = (component) => {
-            const num = parseInt(component, 10);
-            return 0 <= num && num <= 255;
-        };
-        if (ipComponents[0] === "127" &&
-            inRange(ipComponents[1]) &&
-            inRange(ipComponents[2]) &&
-            inRange(ipComponents[3]) &&
-            ipComponents.length === 4) {
-            return;
-        }
-    }
-    throw new property_provider_1.CredentialsProviderError(`URL not accepted. It must either be HTTPS or match one of the following:
-  - loopback CIDR 127.0.0.0/8 or [::1/128]
-  - ECS container host 169.254.170.2
-  - EKS container host 169.254.170.23 or [fd00:ec2::23]`, { logger });
-};
-exports.checkUrl = checkUrl;