feat(pascal): add Pascal language server support

Add support for Free Pascal/Lazarus projects using pasls.

Features:
- Auto-download pasls binary for Linux, macOS, and Windows
- Platform detection for x64 and arm64 architectures
- Support for FPC environment variables (PP, FPCDIR)

CI: Add FPC compiler installation (fpc-ootb for Windows)

Includes test repository and unit tests.

test/resources/repos/pascal/test_repo/.gitignore

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+backup/
+*.o
+*.ppu
+*.exe
+*.lps
+*.compiled
+__history/
+__recovery/

test/resources/repos/pascal/test_repo/lib/helper.pas

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+unit Helper;
+
+{$mode objfpc}{$H+}
+
+interface
+
+uses
+  Classes, SysUtils;
+
+type
+  { THelper - A helper class with utility functions }
+  THelper = class
+  public
+    class function FormatString(const Template: string; const Args: array of const): string;
+    class function IsEven(Number: Integer): Boolean;
+  end;
+
+{ Standalone helper functions }
+function GetHelperMessage: string;
+function MultiplyNumbers(A, B: Integer): Integer;
+procedure LogMessage(const Msg: string);
+
+implementation
+
+{ THelper }
+
+class function THelper.FormatString(const Template: string; const Args: array of const): string;
+begin
+  Result := Format(Template, Args);
+end;
+
+class function THelper.IsEven(Number: Integer): Boolean;
+begin
+  Result := (Number mod 2) = 0;
+end;
+
+{ Standalone functions }
+
+function GetHelperMessage: string;
+begin
+  Result := 'Hello from Helper unit!';
+end;
+
+function MultiplyNumbers(A, B: Integer): Integer;
+begin
+  Result := A * B;
+end;
+
+procedure LogMessage(const Msg: string);
+begin
+  WriteLn('[LOG] ', Msg);
+end;
+
+end.

test/resources/repos/pascal/test_repo/main.pas

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+unit Main;
+
+{$mode objfpc}{$H+}
+
+interface
+
+uses
+  Classes, SysUtils, Helper;
+
+type
+  { TUser - A simple user class }
+  TUser = class
+  private
+    FName: string;
+    FAge: Integer;
+  public
+    constructor Create(const AName: string; AAge: Integer);
+    destructor Destroy; override;
+
+    function GetInfo: string;
+    procedure UpdateAge(NewAge: Integer);
+
+    property Name: string read FName write FName;
+    property Age: Integer read FAge write FAge;
+  end;
+
+  { TUserManager - Manages multiple users }
+  TUserManager = class
+  private
+    FUsers: TList;
+  public
+    constructor Create;
+    destructor Destroy; override;
+
+    procedure AddUser(User: TUser);
+    function GetUserCount: Integer;
+    function FindUserByName(const AName: string): TUser;
+  end;
+
+{ Helper functions }
+
+/// Calculates the sum of two integers.
+/// @param A First integer value
+/// @param B Second integer value
+/// @returns The sum of A and B
+function CalculateSum(A, B: Integer): Integer;
+procedure PrintMessage(const Msg: string);
+
+implementation
+
+{ TUser implementation }
+
+constructor TUser.Create(const AName: string; AAge: Integer);
+begin
+  inherited Create;
+  FName := AName;
+  FAge := AAge;
+end;
+
+destructor TUser.Destroy;
+begin
+  inherited Destroy;
+end;
+
+function TUser.GetInfo: string;
+begin
+  Result := Format('Name: %s, Age: %d', [FName, FAge]);
+end;
+
+procedure TUser.UpdateAge(NewAge: Integer);
+begin
+  FAge := NewAge;
+end;
+
+{ TUserManager implementation }
+
+constructor TUserManager.Create;
+begin
+  inherited Create;
+  FUsers := TList.Create;
+end;
+
+destructor TUserManager.Destroy;
+var
+  i: Integer;
+begin
+  for i := 0 to FUsers.Count - 1 do
+    TUser(FUsers[i]).Free;
+  FUsers.Free;
+  inherited Destroy;
+end;
+
+procedure TUserManager.AddUser(User: TUser);
+begin
+  FUsers.Add(User);
+end;
+
+function TUserManager.GetUserCount: Integer;
+begin
+  Result := FUsers.Count;
+end;
+
+function TUserManager.FindUserByName(const AName: string): TUser;
+var
+  i: Integer;
+begin
+  Result := nil;
+  for i := 0 to FUsers.Count - 1 do
+  begin
+    if TUser(FUsers[i]).Name = AName then
+    begin
+      Result := TUser(FUsers[i]);
+      Exit;
+    end;
+  end;
+end;
+
+{ Helper functions }
+
+function CalculateSum(A, B: Integer): Integer;
+begin
+  Result := A + B;
+end;
+
+procedure PrintMessage(const Msg: string);
+begin
+  WriteLn(Msg);
+end;
+
+end.