Haskell-based compiler 0.6.5 crashes when compiling a package that has a summary field >= 80 chars

Example:

{
    "type": "package",
    "platform": "common",
    "name": "example/package",
    "license": "BSD-3-Clause",
    "summary": "this summary line is not that long... but it is longer than expected at 80 chars",
    "source-directories": [
        "src"
    ],
    "version": "1.0.0",
    "exposed-modules": [
            "Main"
    ],
    "gren-version": "0.6.0 <= v < 0.7.0",
    "dependencies": {
        "gren-lang/core": "7.4.0 <= v < 8.0.0"
    }
}

"gren make" produces:

gren: DecodeProblem "{\"command\":\"make\",\"optimize\":false,\"sourcemap .... 
<snipped>

\"summary\":\"this summary line is not that long... but it is longer than expected at 80 chars\"
<snipped>

(Field "project-outline" (Field "summary" (Failure (Region (Position 1 266) (Position 1 348)) InvalidInput)))
CallStack (from HasCallStack):  error, called at terminal/Main.hs:30:13 in gren-0.6.5-inplace-gren:Main
HasCallStack backtrace:
  collectBacktraces, called at libraries/ghc-internal/src/GHC/Internal/Exception.hs:169:13 in ghc-internal:GHC.Internal.Exception
  toExceptionWithBacktrace, called at libraries/ghc-internal/src/GHC/Internal/Exception.hs:204:5 in ghc-internal:GHC.Internal.Exception  error, called at terminal/Main.hs:30:13 in gren-0.6.5-inplace-gren:Main

Example project is in this git repo: https://github.com/gilramir/gren-bug-reports

$ cd 2026-06-28-summary
$ gren make

If the summary field is 79 characters, it's fine.
This doesn't crash for gren.json type "application", I guess because "summary" isn't used then; it must only be used for "package" types.

Reproduce the crash with gren make in the linked gren-bug-reports example project, using the package summary lengths described in the report. Start from the reported failure at terminal/Main.hs:30:13 and the summary decoding path. Done means package summaries at or above 80 characters no longer crash, while the existing 79-character case continues to work.