docs: rewrite installation page and add OSS install to contribution g…

[PrathamSikka24]

…uide

• Rewrote server/installation_tabs.md: new intro, numbered sections, login tabs (browser/manual/API key), install output block, updated post-login copy
• Appended OSS install section to keploy-explained/dev-guide.md with Linux/macOS/Windows tabs; cleaned up heading emoji and OPEN SOURCE label
• Added server/installation entry to version-4.0.0 sidebar
• Fixed window.gtag runtime error: stub in headTags + disable gtag in dev

What has changed?

Please include a summary of the change.

This PR Resolves #(issue)

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue).
• New feature (non-breaking change which adds functionality).
• Breaking change (fix or feature that would cause existing functionality to not work as expected).
• Documentation update (if none of the other choices apply).

How Has This Been Tested?

Please run npm run build and npm run serve to check if the changes are working as expected. Please include screenshots of the output of both the commands. Add screenshots/gif of the changes if possible.

Checklist:

• My code follows the style guidelines of this project.
• I have performed a self-review of my own code.

[Copilot]

Pull request overview

This PR updates the v4.0.0 documentation to improve installation and contribution guidance, and adjusts Docusaurus configuration to avoid window.gtag runtime errors.

Changes:

• Rewrote the v4.0.0 “Installing Keploy” doc to focus on CLI install + login flows (browser/manual/API key).
• Added an “Installing the Open Source Build” section to the v4.0.0 contribution guide, including OS-specific tabs.
• Updated the v4.0.0 sidebar to include the new Installation doc entry, and adjusted Docusaurus config to stub window.gtag + disable gtag outside production.

Reviewed changes

Copilot reviewed 4 out of 5 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
versioned_sidebars/version-4.0.0-sidebars.json	Adds a sidebar entry for the new Installation doc in v4.0.0.
versioned_docs/version-4.0.0/server/installation_tabs.md	Rewrites the installation page content and adds login method tabs.
versioned_docs/version-4.0.0/keploy-explained/dev-guide.md	Appends OSS installation guidance with OS tabs (MDX content).
docusaurus.config.js	Adds a window.gtag stub in headTags and conditionally disables gtag outside production.
.gitignore	Ignores additional local .claude/* directories.

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[Copilot]

The new OSS install section adds MDX import ... statements after existing Markdown content. In Docusaurus/MDX, ESM imports must be at the top level before any rendered content; otherwise the file can fail to compile. Move these imports to the top of the document (right after the frontmatter) or refactor the section to avoid late imports.

[amaan-bhati]

Thank you for tackling multiple issues in one PR - the installation page rewrite, the OSS install section in the dev guide, and the window.gtag runtime error fix are all genuinely useful improvements. The gtag stubbing approach (define window.dataLayer and window.gtag in headTags so calls don't throw before the real script loads) is the right fix for that class of runtime error.

Issues to be Considered:

• The .gitignore additions (.claude/qa-agent/ and .claude/commands/) are Claude Code tool-specific paths that belong in a personal global gitignore (~/.gitignore_global) rather than the repository's shared .gitignore. Adding editor or AI-tool local directories to the project gitignore can cause friction for contributors using different tooling.

• The installation_tabs.md rewrite removes the ProductTier component (<ProductTier tiers="Open Source" offerings="Self-Hosted, Dedicated" />) and the full tab-based OS selection UI. This is a substantial UX change - the original page guided users through Linux/macOS/Windows and Docker paths via tabs. The new version appears simpler but the diff shows the tab structure is no longer present. Please confirm this is intentional and that the replacement content covers all the same OS paths.

• The PR description still contains the unfilled placeholder "Please include a summary of the change. This PR Resolves #(issue)" from the PR template. Please fill this in so reviewers can understand the decisions made in the rewrite without having to read every line of the diff.

• Disabling gtag in process.env.NODE_ENV === "production" ? { ... } : false is correct for development, but please verify this doesn't silently disable analytics in preview/staging deployments where NODE_ENV may also be set to production. A quick check of the deploy environment variables would confirm.

• The dev-guide.md OSS install section uses StartKeploy and StartKeployDocker components imported inline inside the MDX content. Please verify these imports don't conflict with the existing imports already at the top of the file if any exist, since duplicate imports in MDX can cause build errors.

The core intent of this PR is solid. Cleaning up the PR description and clarifying the installation_tabs.md scope are the most important items before this moves forward.