Lpo files contain absolute positions

[Alidra]

In Improvements and new features for indexing#1290, the sig_state_of_require has been changed to Allow the --require flag to be used multiple times with the search and websearch commands.
However, this breaks the LSP server.
To reproduce :
In Vscode open any LP file (for instance tests/OK/apply.lp)
add require open Stdlib.Prop; at the begining of any the file
go one step forward
in the terminal you will see somethins like :
file:///......../lambdapi/tests/OK/apply.lp:1:0-66/...../.opam/default/.opam-switch/build/lambdapi-stdlib.1.3.1/Prop.lp cannot be mapped under the library root. Consider adding a package file under your source tree, or use the [--map-dir] option.

[sacerdot]

I confirm the bug, but sig_state_of_require is not the culprit. The culprit is due to the usage in the LSP of a "local" file that is actually installed using lambdapi install that relocates the file. The .lpo were not thought to be relocatable when implementing search (and indeed they are not): they concaint positions with absolute paths. The exception is raised when trying to access a file that has been moved. In particular this is required: 1) to synthesize a QID for rule names that have none ; 2) to show the query results

[fblanqui]

The complete error message in VSCode is:

file:///home/blanqui/src/lambdapi/tests/OK/apply.lp:1:0-23/home/blanqui/.opam/5.5.0/.opam-switch/build/lambdapi-stdlib.1.4.0/Prop.lp cannot be mapped under the library root.
Consider adding a package file under your source tree, or use the [--map-dir] option.

In Emacs, I get:

Syntax error. Expected: "open", "private", "qualified identifier".

Strange...

[fblanqui]

Concerning lpo files, what about using relative positions? The absolute position could be obtained on the fly by using file_of_path?

[fblanqui]

With #1455, I get in VSCode:

/home/blanqui/.LPSearch.db: No such file or directory.
Type "lambdapi index --help" to learn how to create the index.
file:///home/blanqui/src/lambdapi/tests/OK/apply.lp:1:0-23"/home/blanqui/.opam/5.5.0/.opam-switch/build/lambdapi-stdlib.1.4.0/Prop.lp" cannot be mapped under the library root.
Consider adding a package file under your source tree, or use the [--map-dir] option.

Note that there is no space or newline between the position and the error message.