feat(sdk): adds configurable max manifest sizes

[imdominicreed]

Proposed Changes

• Allows configurable max manifest size so large TDFs can be decrypted.

Checklist

• I have added or updated unit tests
• I have added or updated integration tests (if appropriate)
• I have added or updated documentation

Testing Instructions

[gemini-code-assist]

Summary of Changes

Hello @imdominicreed, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request implements a new feature in the TDF SDK that allows for the configuration of a maximum manifest size when loading TDF files. This enhancement provides greater control over resource consumption and helps prevent potential issues that could arise from processing unusually large or malformed manifests, thereby improving the robustness and security of the SDK.

Highlights

• Configurable Manifest Size: Introduced a new "manifestMaxSize" field in the "TDFReader" struct, allowing the maximum size of a TDF manifest to be configured.
• New Configuration Options: Added "WithTDFManifestMaxSize" for "archive.NewTDFReader" and "WithMaxManifestSize" for "TDFReaderConfig" to enable setting the manifest size limit.
• Default Manifest Size: A default maximum manifest size of 10MB is now applied when creating a "TDFReaderConfig".
• Integration with SDK: The "SDK.LoadTDF" method now utilizes the configurable manifest size when loading TDF files.
• New Test Cases: Comprehensive unit tests have been added to verify the correct behavior of the manifest size limits, including scenarios where manifests are just below or above the configured maximum.

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Manifests now capped, Size controlled, no overflow, Code runs safe and sound.

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[gemini-code-assist]

Code Review

This pull request introduces a configurable maximum manifest size for TDF files, which is a valuable feature for handling large manifests. The implementation using the functional options pattern is well-done. However, I've found a couple of issues: a misleading error message due to a copy-paste error, and a new test case that is fundamentally flawed in its approach. My review includes suggestions to correct these issues.

[Copilot]

Pull Request Overview

This PR adds support for configurable maximum manifest sizes in TDF decryption, allowing users to decrypt large TDFs with manifests exceeding the previous hard-coded 10 MB limit. The implementation introduces a new WithMaxManifestSize option that can be passed to LoadTDF, which propagates the size limit through the configuration layers to the archive reader.

Key changes:

• Added WithMaxManifestSize() option function for TDF reader configuration
• Refactored LoadTDF() to initialize configuration before creating the TDF reader to pass the max size parameter
• Updated the internal archive reader to accept configurable manifest size limits via options pattern

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

File	Description
sdk/tdf_config.go	Adds defaultMaxManifestSize constant (10 MB), maxManifestSize field to TDFReaderConfig, and WithMaxManifestSize() option function for configuring the limit
sdk/tdf.go	Refactors LoadTDF() to initialize TDFReaderConfig earlier so the max manifest size can be passed to archive.NewTDFReader()
sdk/internal/archive/tdf3_reader.go	Adds manifestMaxSize field to TDFReader struct, WithTDFManifestMaxSize() option function, and updates NewTDFReader() to accept options
sdk/tdf_test.go	Adds Test_LargeManifest_WithMaxManifest() to verify that manifests below the limit load successfully and manifests above the limit are rejected

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