fix: max blob size and other encryption tests

[alanshaw]

Depends on:

• fix: align MaxBlobSize with Piri DefaultMaxPaddedSize libforge#65

Refs:

• https://linear.app/filecoin-foundation/issue/FIL-495
• https://linear.app/filecoin-foundation/issue/FIL-483

[Copilot]

🟡 Changes recommended

The new patternReader.Read implementation in itest/stack_test.go uses an int64 slice index and will not compile.

Once you've addressed the issues Copilot identified, you can request another Copilot review.

Pull request overview

Adds/extends integration coverage around encryption behavior and large-object limits, and adjusts max_blob_size defaults/validation so encrypted envelopes remain shippable to piri under its piece cap.

Changes:

• Add new forge-mode encryption integration suite (TestForgeEncryption) and a gated 5 GiB max-part test, plus supporting harness utilities.
• Update default blob sizing to account for encryption envelope overhead; add config validation and unit tests to fail fast on unshippable max_blob_size values.
• Update docs and CI itest job settings (timeouts/disk space) to accommodate the new big-part coverage.

File summaries

File	Description
itest/stack_test.go	Adds spool inspection/tamper helpers, pattern streaming reader, and a no-timeout S3 client for very large uploads
itest/README.md	Documents new encryption/max-part itest coverage and gating
itest/forge_encryption_test.go	New encryption and large-part integration tests (incl. tamper rejection and delete release verification)
itest/forge_delete_test.go	Removes duplicated waitForPiriLog helper now centralized in stack harness
config/config.go	Validates max_blob_size against encrypted-envelope size vs network ceiling
config/config_test.go	Adds regression test for max_blob_size validation behavior
bucket/chunker.go	Changes DefaultMaxBlobSize derivation to reserve encryption envelope allowance under piri’s cap
bucket/chunker_test.go	Pins envelope-fit derivation with a unit test
blockstore/store.go	Updates comments to reflect ~254 MiB default sizing
blockstore/spool.go	Updates comments to reflect ~254 MiB default sizing
docs/architecture.md	Updates architecture doc to reflect the corrected piece cap and default sizing rationale
.github/workflows/go-test.yml	Increases itest timeouts, frees runner disk, and enables the gated big itest in CI
go.mod	Bumps fil-forge/libforge dependency (per PR dependency note)
go.sum	Updates checksums for the bumped fil-forge/libforge version

Review details

• Files reviewed: 13/14 changed files
• Comments generated: 2
• Review effort level: Lite

---

💡 Add a code-review agent skill or configure MCP servers for context-aware, tailored reviews. Learn more in the docs.