esi pins fastly ^0.12, which blocks the fastly 0.13 upgrade

[aram356]

The esi crate declares fastly = "^0.12". EdgeZero moves to fastly 0.13 (stackpop/edgezero#366), and both land in trusted-server-adapter-fastly, so the graph carries two incompatible copies of the same types:

fastly 0.13.1  <- edgezero-adapter-fastly
fastly 0.12.1  <- esi 0.7.2

crates/trusted-server-adapter-fastly/src/esi_assembly.rs passes fastly::http::Response and Request across that boundary, so it fails to compile:

error[E0308]: mismatched types
   --> crates/trusted-server-adapter-fastly/src/esi_assembly.rs:96:9
error[E0631]: type mismatch in closure arguments
   --> crates/trusted-server-adapter-fastly/src/esi_assembly.rs:124:65

ESI is unconditional in that adapter (not feature-gated), so it cannot be sidestepped.

The fix is one line, upstream

esi needs no source changes. Cloning fastly/esi at v0.7.2 and changing only the manifest range:

-fastly = "^0.12"
+fastly = "^0.13"

cargo check -p esi --target wasm32-wasip1 passes clean. With that patched in locally, the entire trusted-server workspace compiles, including the Fastly adapter.

Status upstream

• fastly/esi main still reads fastly = "^0.12".
• Published esi 0.7.2 declares ^0.12 (confirmed via the crates.io dependency API).
• No open PR addresses it. fastly/esi#60 is the v0.7.1 to v0.7.2 release bump and touches only the workspace version and lockfile.

Options

1. Open a one-line PR against fastly/esi and wait for a release.
2. Carry the fix on the existing stackpop/esi fork and reference it from [patch.crates-io] until upstream releases. Note the fork's main is behind upstream (missing v0.7.1 and v0.7.2), so it should branch from upstream v0.7.2.

Blocks #1123

[aram356]

Verified end to end with the one-line fix applied locally, on Rust 1.98.1 and Viceroy 0.21.0.

Cloned fastly/esi at v0.7.2, changed only the manifest range:

-fastly = "^0.12"
+fastly = "^0.13"

No source changes to esi. cargo check -p esi --target wasm32-wasip1 compiles clean.

With that referenced from [patch.crates-io] in trusted-server, both Fastly gates pass:

• cargo clippy-fastly — clean under -D warnings
• cargo test-fastly — 166 adapter tests (ESI assembly included), 2290 core, 2 js, 21 openrtb, 3 doctests; 0 failed

So the version range is genuinely the only obstacle, and the resulting build is exercised rather than merely compiling.