perf!: remove bound-caching from Type, do in SumType::General instead

[acl-cqc]

Type currently caches the TypeBound alongside its Term; there are only three possible Term:: variants, and the cache is pretty much redundant in two (and a half):

• Term::RuntimeFunction --> we know it's TypeBound::Copyable
• Term::RuntimeExtension --> the ExtensionType also stores the bound, so we can just read that
• Term::RuntimeSum depends on the SumType
  • SumType::Unary --> we know it's TypeBound::Copyable
  • SumType::General --> the only case where we actually need it

Hence, make SumType::General store a struct GeneralSum, with bound and rows (these are kept private to avoid mutating rows without updating the bound). And remove the cache in Type.

BREAKING CHANGE: any match on SumType::General {rows} ...rows... becomes SumType::General(gs) ...gs.rows()... ; construct GeneralSum with ::new

[codspeed-hq]

Merging this PR will improve performance by 17.69%

⚡ 1 improved benchmark
✅ 28 untouched benchmarks
⏩ 6 skipped benchmarks¹

Performance Changes

	Benchmark	BASE	HEAD	Efficiency
⚡	construction	20.2 µs	17.2 µs	+17.69%

---

_{Comparing acl/boundless_type (417c6eb) with main (d372743)}

Footnotes

1. 6 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[codecov]

Codecov Report

❌ Patch coverage is 95.38462% with 3 lines in your changes missing coverage. Please review.
✅ Project coverage is 81.09%. Comparing base (d372743) to head (417c6eb).

Files with missing lines	Patch %	Lines
hugr-core/src/types.rs	93.02%	1 Missing and 2 partials ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #3022   +/-   ##
=======================================
  Coverage   81.09%   81.09%           
=======================================
  Files         241      241           
  Lines       45054    45060    +6     
  Branches    38822    38828    +6     
=======================================
+ Hits        36536    36541    +5     
  Misses       6542     6542           
- Partials     1976     1977    +1     

Flag	Coverage Δ
python	88.89% <ø> (ø)
rust	79.84% <95.38%> (+<0.01%)	⬆️

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[acl-cqc]

Does this need a comment to say, recompute the bound?

[hugrbot]

This PR contains breaking changes to the public Rust API.

cargo-semver-checks summary

    Building hugr v0.27.1 (current)
     Built [  35.089s] (current)
   Parsing hugr v0.27.1 (current)
    Parsed [   0.004s] (current)
  Building hugr v0.27.1 (baseline)
     Built [  34.568s] (baseline)
   Parsing hugr v0.27.1 (baseline)
    Parsed [   0.004s] (baseline)
  Checking hugr v0.27.1 -> v0.27.1 (assume minor change)
   Checked [   0.012s] 196 checks: 196 pass, 56 skip
   Summary no semver update required
  Finished [  72.609s] hugr
  Building hugr-cli v0.27.1 (current)
     Built [  29.186s] (current)
   Parsing hugr-cli v0.27.1 (current)
    Parsed [   0.006s] (current)
  Building hugr-cli v0.27.1 (baseline)
     Built [  28.788s] (baseline)
   Parsing hugr-cli v0.27.1 (baseline)
    Parsed [   0.006s] (baseline)
  Checking hugr-cli v0.27.1 -> v0.27.1 (assume minor change)
   Checked [   0.015s] 196 checks: 196 pass, 56 skip
   Summary no semver update required
  Finished [  59.668s] hugr-cli
  Building hugr-core v0.27.1 (current)
     Built [  24.901s] (current)
   Parsing hugr-core v0.27.1 (current)
    Parsed [   0.086s] (current)
  Building hugr-core v0.27.1 (baseline)
     Built [  24.797s] (baseline)
   Parsing hugr-core v0.27.1 (baseline)
    Parsed [   0.078s] (baseline)
  Checking hugr-core v0.27.1 -> v0.27.1 (assume minor change)
   Checked [   0.238s] 196 checks: 195 pass, 1 fail, 0 warn, 56 skip

--- failure enum_struct_variant_changed_kind: An enum struct variant changed kind ---

Description:
A pub enum's struct variant with at least one pub field has changed to a different kind of enum variant, breaking access to its pub fields.
      ref: https://doc.rust-lang.org/reference/items/enumerations.html
     impl: https://github.com/obi1kenobi/cargo-semver-checks/tree/v0.47.0/src/lints/enum_struct_variant_changed_kind.ron

Failed in:
variant SumType::General in /home/runner/work/hugr/hugr/PR_BRANCH/hugr-core/src/types.rs:180

   Summary semver requires new major version: 1 major and 0 minor checks failed
  Finished [  51.390s] hugr-core
  Building hugr-llvm v0.27.1 (current)
     Built [  29.446s] (current)
   Parsing hugr-llvm v0.27.1 (current)
    Parsed [   0.012s] (current)
  Building hugr-llvm v0.27.1 (baseline)
     Built [  29.563s] (baseline)
   Parsing hugr-llvm v0.27.1 (baseline)
    Parsed [   0.012s] (baseline)
  Checking hugr-llvm v0.27.1 -> v0.27.1 (assume minor change)
   Checked [   0.039s] 196 checks: 196 pass, 56 skip
   Summary no semver update required
  Finished [  60.094s] hugr-llvm
  Building hugr-model v0.27.1 (current)
     Built [  10.715s] (current)
   Parsing hugr-model v0.27.1 (current)
    Parsed [   0.017s] (current)
  Building hugr-model v0.27.1 (baseline)
     Built [  10.711s] (baseline)
   Parsing hugr-model v0.27.1 (baseline)
    Parsed [   0.016s] (baseline)
  Checking hugr-model v0.27.1 -> v0.27.1 (assume minor change)
   Checked [   0.029s] 196 checks: 196 pass, 56 skip
   Summary no semver update required
  Finished [  22.045s] hugr-model
  Building hugr-persistent v0.6.1 (current)
     Built [  22.201s] (current)
   Parsing hugr-persistent v0.6.1 (current)
    Parsed [   0.008s] (current)
  Building hugr-persistent v0.6.1 (baseline)
     Built [  23.346s] (baseline)
   Parsing hugr-persistent v0.6.1 (baseline)
    Parsed [   0.007s] (baseline)
  Checking hugr-persistent v0.6.1 -> v0.6.1 (assume minor change)
   Checked [   0.012s] 196 checks: 196 pass, 56 skip
   Summary no semver update required
  Finished [  46.330s] hugr-persistent

[acl-cqc]

Note this allows bypassing the update of the bound, so we keep it crate-private (and use it only for things where we are sure the bound doesn't change - namely, extension resolution)

[acl-cqc]

This temporary debris from #2895 has now moved to a proper home in Term::validate