…var/let symbols
fixes#22939fixes#16890
Besides, it was applied to let/const/var with pragmas, now it is
universally applied.
```nim
{.push exportc.}
proc foo =
let bar = 12
echo bar
{.pop.}
```
For example, the `bar` variable will be affected by `exportc`.
* fixes#19795; remove parse pipeline
* isScript
* fixes nimscriptapi
* don't touch reorder
* check script
* fixes tests
* it seems implicit imports of system cause troubles
* access the first child of `nkStmtList`
* ignore comments
* minor messages
* perhaps increases hloLoopDetector
* the module is a stmtList, which changes the errors
* fixes nimdoc
* fixes tlinter
* fixes nim secret tests
* fixes arc_misc
* fixes nim secret tests again
* safe; fixes one more test
* GlobalError is the root cause too
* fixes parsing errors
* put emit types to the cfsForwardTypes section
* fixes#11852; `{.push checks:off}` now works in procs
* disable navigator
* fixes nimdoc
* add tests for JS
* fixes nimsuggest
* `nim doc --backend:js|cpp...`
`nim doc --doccmd:'-d:foo --threads:on'`
`nim r --backend:cpp...` (implies --run --usenimcache)
* --usenimcache works with all targets
* --docCmd:skip now skips compiling snippets; 50X speedup for doc/manual.rst
