fix(compute): use -gc=precise for TinyGo default build command (#1480)

[Tyagiquamar]

Description

Updates the default fallback build command for TinyGo in \pkg/commands/compute/language_go.go\ from -gc=conservative\ to -gc=precise. The precise collector provides more accurate and efficient garbage collection in Wasm builds compared to conservative GC.

Fixes #1480.

Verification

• Ran \gofmt -l -w pkg/commands/compute/language_go.go\
• Ran \go test -v ./pkg/commands/compute/...\ in Docker \golang:1.26-bookworm\ (all tests pass)

[rcaril]

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