Throw internal/compiler errors instead Error when possible

[jubnzv]

Closes #645

I have replaced throw Error with throwInternalCompilerError in most cases, as that's essentially how the compiler should behave. If the user encounters an "impossible" case, they should definitely be encouraged to report it.

Otherwise, if we encounter this kind of error while using the compiler API in a tool, we should understand that we are using it incorrectly.

Note that I didn't modify the old backend, as it will be rewritten anyway.

• I have updated CHANGELOG.md
• I have documented my contribution in Tact Docs: https://github.com/tact-lang/tact-docs/pull/PR-NUMBER
• I have added tests to demonstrate the contribution is correctly implemented: this usually includes both positive and negative tests, showing the happy path(s) and featuring intentionally broken cases
• I have run all the tests locally and no test failure was reported
• I have run the linter, formatter and spellchecker
• I did not do unrelated and/or undiscussed refactorings

[anton-trunov]

Yay!

[anton-trunov]

Oh, btw, let's add the Tact errors to index.ts as well in this PR

[Gusarich]

It's now less informative in some cases. For example, when trying to compile non-existing project source:

💼 Compiling project getters ...
Tact compilation failed
Error
    at throwCompilationError (/Users/daniil/Coding/tact/src/errors.ts:91:11)
    at resolveImports (/Users/daniil/Coding/tact/src/imports/resolveImports.ts:28:30)
    at precompile (/Users/daniil/Coding/tact/src/pipeline/precompile.ts:18:36)
    at build (/Users/daniil/Coding/tact/src/pipeline/build.ts:73:25)
    at run (/Users/daniil/Coding/tact/src/node.ts:130:34)
    at async /Users/daniil/Coding/tact/scripts/prepare.ts:20:31
Error: Tact projects compilation failed
    at /Users/daniil/Coding/tact/scripts/prepare.ts:24:19
error Command failed with exit code 1.

while before it would throw Could not find entrypoint XXX.

I think the problem is here, because it ignores message in case if no source location was provided.