Unreducible production after conflict resolution incorrectly leading to further conflicts

NeoBeaver does not remove productions during conflict resolution which can lead to false positive errors when checking conflicts.

For example, when a shift/reduce conflict is resolved by choosing the SHIFT action, the reduce action should be removed from the transition table and not cause other conflicts.

Here is a small grammar with only one conflict but NeoBeaver reports two conflicts:

%goal expr;

%terminals LPAREN, RPAREN, ASTERISK, ID, INT;

expr =
    name
  | expr_nn
  ;
expr_nn =
    num
  | LPAREN expr RPAREN
  | LPAREN name RPAREN
  | LPAREN name ptr? RPAREN expr
  ;
ptr =
    ASTERISK
  | ptr ASTERISK
  ;
num = INT;
name = ID;

NeoBeaver reports these conflicts:

SHIFT/REDUCE:
  SHIFT RPAREN                          
  REDUCE expr -> name

REDUCE/REDUCE:
  REDUCE ptr$opt ->
  REDUCE expr -> name

If the SHIFT action is chosen in the SHIFT/REDUCE conflict, then the reduction expr -> name becomes unreachable and will not conflict with ptr$opt ->. In this case the REDUCE/REDUCE conflict is spurious and should not be reported.

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