Feat merge the headers/cookies/querystring info in the first and later request

[LeoLiuYan]

When execute tools/call, it lost the first request metadata include headers/cookies/querystring. In this PR, we merge the metadata in requests, and use the latest request metadata to ovrride the first request.

Summary by Sourcery

Capture and propagate HTTP request metadata across sessions and tool invocations to ensure headers, query parameters, and cookies persist and merge correctly.

New Features:

• Store initial request headers, query parameters, and cookies in a new RequestInfo attached to session metadata.
• Merge stored metadata with each subsequent request, overriding values with the latest request data.

Enhancements:

• Extend PrepareTemplateContext to accept RequestInfo and merge initial and current request metadata before rendering.
• Refactor mcpproxy fetch and invoke functions and core server handlers to pass session.Connection and propagate RequestInfo through tool execution APIs.

[sourcery-ai]

Reviewer's Guide

This PR centralizes the capture and propagation of request metadata (headers, query parameters, cookies) by introducing a RequestInfo struct, merging first and later request data, and threading the session.Connection through all tool-fetching and invocation paths so templates can use the complete metadata.

File-Level Changes

Change	Details	Files
Capture initial request metadata into the session for SSE connections	Add RequestInfo struct to session package Populate RequestInfo (headers, query, cookies) in handleSSE Attach RequestInfo to session.Meta	internal/mcp/session/session.go internal/core/sse.go
Merge stored metadata with each new request when rendering templates	Extend PrepareTemplateContext to accept RequestInfo Preload existing headers, queries, cookies before applying the new request Use merged metadata in template context	internal/template/renderer.go
Propagate session.Connection through server handlers and core tool invocations	Inject conn into FetchToolList and InvokeTool calls in SSE and streamable handlers Update executeHTTPTool to accept conn Pass conn to invokeHTTPTool in core	internal/core/sse.go internal/core/streamable.go internal/core/tool.go
Adapt mcpproxy transport functions to thread metadata into templates	Change FetchToolList and InvokeTool signatures to include conn Import session package and extract Meta().Request Pass RequestInfo into PrepareTemplateContext in stdio, SSE, streamable proxies	internal/core/mcpproxy/stdio.go internal/core/mcpproxy/sse.go internal/core/mcpproxy/streamable.go

---

Tips and commands

Interacting with Sourcery

• Trigger a new review: Comment @sourcery-ai review on the pull request.
• Continue discussions: Reply directly to Sourcery's review comments.
• Generate a GitHub issue from a review comment: Ask Sourcery to create an
  issue from a review comment by replying to it. You can also reply to a
  review comment with @sourcery-ai issue to create an issue from it.
• Generate a pull request title: Write @sourcery-ai anywhere in the pull
  request title to generate a title at any time. You can also comment
  @sourcery-ai title on the pull request to (re-)generate the title at any time.
• Generate a pull request summary: Write @sourcery-ai summary anywhere in
  the pull request body to generate a PR summary at any time exactly where you
  want it. You can also comment @sourcery-ai summary on the pull request to
  (re-)generate the summary at any time.
• Generate reviewer's guide: Comment @sourcery-ai guide on the pull
  request to (re-)generate the reviewer's guide at any time.
• Resolve all Sourcery comments: Comment @sourcery-ai resolve on the
  pull request to resolve all Sourcery comments. Useful if you've already
  addressed all the comments and don't want to see them anymore.
• Dismiss all Sourcery reviews: Comment @sourcery-ai dismiss on the pull
  request to dismiss all existing Sourcery reviews. Especially useful if you
  want to start fresh with a new review - don't forget to comment
  @sourcery-ai review to trigger a new review!

Customizing Your Experience

Access your dashboard to:

• Enable or disable review features such as the Sourcery-generated pull request
  summary, the reviewer's guide, and others.
• Change the review language.
• Add, remove or edit custom review instructions.
• Adjust other review settings.

Getting Help

• Contact our support team for questions or feedback.
• Visit our documentation for detailed guides and information.
• Keep in touch with the Sourcery team by following us on X/Twitter, LinkedIn or GitHub.

[sourcery-ai]

Hey @LeoLiuYan - I've reviewed your changes and they look great!

Here's what I looked at during the review

• 🟡 General issues: 1 issue found
• 🟢 Testing: all looks good
• 🟢 Documentation: all looks good

---

Sourcery is free for open source - if you like our reviews please consider sharing them ✨

• X
• Mastodon
• LinkedIn
• Facebook

_{Help me be more useful! Please click 👍 or 👎 on each comment and I'll use the feedback to improve your reviews.}

[LeoLiuYan]

@iFurySt PTAL.

[iFurySt]

LGTM! Thanks!