Remove unused legacy token BrokenResolvable and cleanup

[ivov]

The BrokenResolvable token was added to support a requirement that was later dropped, so this token is unused. I'm not clear on why BrokenResolvable is currently causing so many tests to fail on master. I wrote tests specifically for this token and Codemirror's test harness does not allow running a subset of tests, therefore I expect these were all passing back when v1 of this lib was released. But there was no CI to block merging in case of failing tests. In any case, this token is unneeded, so we can remove and simplify.

Once this lib is in the monorepo, regressions will be caught by test script runs.

npm run test

> codemirror-lang-n8n-expression@0.2.0 test
> npm run prepare && mocha test/test.js


> codemirror-lang-n8n-expression@0.2.0 prepare
> rollup -c


src/index.ts → dist/index.cjs, ./dist...
created dist/index.cjs, ./dist in 2.3s


  cases
    ✔ Resolvable
    ✔ Empty Resolvable
    ✔ Resolvable of only whitespace
    ✔ No content
    ✔ Plaintext
    ✔ Plaintext of single-brace-wrapped text
    ✔ Plaintext then Resolvable
    ✔ Resolvable then Plaintext
    ✔ Plaintext then Resolvable then Plaintext
    ✔ Resolvable then Plaintext then Resolvable
    ✔ Plaintext then Resolvable then Plaintext then Resolvable
    ✔ Resolvable then Plaintext then Resolvable then Plaintext
    ✔ Resolvable containing all resolvable chars
    ✔ Resolvable containing single left brace
    ✔ Resolvable containing double left brace
    ✔ Resolvable containing triple left brace
    ✔ Resolvable containing single right brace
    ✔ Resolvable containing escaped double right brace
    ✔ Resolvable containing escaped triple right brace
    ✔ Resolvable containing single-brace-wrapped text with escaping
    ✔ Resolvable containing double-brace-wrapped text with escaping
    ✔ Resolvable containing triple-brace-wrapped text with escaping
    ✔ Resolvable containing single-bracket-wrapped text
    ✔ Resolvable containing double-bracket-wrapped text
    ✔ Resolvable containing triple-bracket-wrapped text
    ✔ Plaintext of one opening brace
    ✔ Plaintext of one opening brace and two closing braces
    ✔ Plaintext then Resolvable with non-ASCII chars then Plaintext


  28 passing (60ms)

[netroy]

Thanks ❤️